FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
COMPLETE SPECIFICATION
(See Section 10 : Rule 13)
TITLE
Process for preparation of UV-absorbing, water-soluble, 2-hydroxy sulphobetaines of cinnamidoalkylamines
APPLICANT
Galaxy Surfactants Ltd.,
C-49/2, TTC Industrial Area, Pawne, Navi-Mumbai 400 703, Maharashtra, India.
A Public Limited Company Registered under Indian Company's Act - 1956
The following specification paiticularly describes the nature of this invention and the manner in which it is to be performed :-

GRANTED
28 MAY 2004

Field of Invention :
This invention relates to a process for manufacture of water-soluble, UV-absorbing sulphobetaines of cinnamidoalkylamines. This invention particularly relates to synthesis of tailor made non-hydrolyzable, non-irritating compounds having substantivity to cotton, wool, skin and hak and UV-radiation absorbing properties useful in soap and toiletries formulation.
Background and Prior Art:
The hannful effects of solar UV-radiation on skin are well known. The UV-B (290 - 320 nm) portion of solar spectrum is largely responsible for erythema (sunburn) and cancer. [M. M. Rieger, Cosmet. Toiletries, 102 (3), 91, (1987); L. Taylor, Skin Cancer Foundation J., 4, (90) (1986)].
Similarly, photodegradative effect of UV-radiation on human hair is well documented. Continuous exposure to sunrays makes human hair color and makes human hair rough, brittle and difficult to comb. UV rays are reported to damage the proteins of cuticles. Prolonged iiradiation results in diminished tensile strength due to breaking of disulphide bonds in keratin. [R. Beyak et al, J. Soc. Cosmet. Chem. 22, 667 - 668 (1971), E. Hoting et al, J. Soc. Cosmet. Chem. 46, 85-99 (1995)]
In addition, UV light is also known to fade garments. [P. C. Screws, Text. Chem. Color, 11, 21 (1987); B. Milliganet al, Polym. Degrad. Stab. 10 (4), 335 (1985)]
A number of UV-absorbing compounds like derivatives of salicylic acid, benzophenones, benzotriazoles, cinnamic acid have been used in personal care products. However, all these molecules suffered from a major disadvantage of lack of substantivity. To make this UV-absorbing moieties more substantive, structural modification have been introduced.
US patent 5,601,811 (1997) describes substantive UV-absorbing quaternary ammonium compounds containing cmnamidoalkylamine and product compositions for detergents, household cleaners and hair and skin personal care products. The synthesis of UV-absorbing sulphobetaines of the present invention employs sodium 3-chloro-2-hydroxy propane sulphonate to quaternize the cinnamidoalkylamines. High water solubility is desirable because these kind of substantive compounds can be formulated in oil-free compositions so that greasy feel of cosmetic preparations based on hydrophobic carrier can be avoided ! Due to their substantive nature constant reapplication of the sunscreen preparation is not necessary in activity like swimming. Hence, the compounds of the present invention are designed to address the need for highly water-soluble yet substantially substantive sunscreen molecules.
Object of the invention :
The main object of the present invention is therefore to synthesize a water-soluble molecule with cinnamido moiety to provide UV-absorption that would be substantive to skin, hair and fabric.

Summary of the invention :
The present invention provides a process for the preparing water-soluble, UV-absorbing sulphobetaines of cinnamidoalkylamine of Formula I,
Formula I

wherein;
R1 is a substituent, selected from H, halo, -OH, -NH2, -N02, -OCH3, -N(CH3)2, alkyl groups containing from 1 to 6 carbon atoms, alkoxy groups containing from 1 to 6 carbon atoms, alkylamino or N.N-dialkylamino groups containing from 1 to 6 carbon atoms;
R2 is selected from hydrogen, alkyl group containing from 1 to 12 carbon atoms;
R3 and R, are independently selected from benzyl, alkyl group containing from 1 to 12 carbon atoms,
n is an integer from 1 to 6;
comprising steps of
reacting 1.0 mole of a compound of Formula II, wherein, R1i is same as that in the compound of said Formula I, and R5 is , -OH, -CI, -0(CH2)pCH3 (p=0 to 3) or an alkyl group with 1 to 4 carbon atoms, with 1.0 to 3.0 moles of a compound of Formula III, wherein, R2, R3, R4 and n are same as that for the compound of said Formula I that is being synthesized, with or without solvent, with or without a basic catalyst, to obtain a compound of Formula IV, wherein, Rl5 R2, R3, R4 and n are same as that for the compound of said Formula I that is being synthesized, till all of the said compound of Formula II has been reacted, the remaining unreacted compound of the said Formula III and the solvent was removed to obtain the said compound of Formula IV;

Formula II

Formula III

Formula IV

ii) carrying out quaternisation on said compound of Formula IV obtained at the end of step (i) with 1.0 mole of sodium 3-chloro-2-hydroxy propane sulphonate compound of Formula V, by stirring under nitrogen, at about 85 to 100°C, in the presence of an water or other protic solvents from about 30 % to 80 % by weight of the reaction mass until CI" reaches the stoichiometric level.
Formula V

Detailed description of the invention :
In the process, the amidification reaction between a compound of the Formula II when R5 = -OH or -0(CH2)pCH3 (p = 0 to 3), with that of Formula III is carried out at from about 120°C to about 200°C, under pressure from about 10 psi to about 100 psi, in the presence of a basic catalyst such as sodium methoxide, sodium hydroxide from 0.25 % to 5.0 % by weight of the reaction mass, to afford the intermediate compound of Formula IV.
From about 0.5 % to 5.0 % w/w of the basic catalyst should be employed. Preferred amount of such catalyst is 1.0 % w/w of total reaction mass. The reaction is conveniently monitored by TLC or HPLC using UV detection. After the complete disappearance of cinnamic acid ester, the excess diamine is distilled off under vacuum.
Alternately, this reaction is carried out in the presence of a basic catalyst such as sodium methoxide, sodium hydroxide from 0.25 % to 5.0 % by weight of the reaction mass under atmospheric pressure, under blanket of nitrogen, with an arrangement for continuous selective removal of lower alcohol formed in the reaction.
Thus, the condensation reaction of one mole of cinnamic acid ester is carried with 1.0 to 3 moles of diamine at 120 to 200°C, preferably at 180°C, for 12 to 36 hours. The amines themselves can

catalyse the reaction, however, the rates are found to be slower as compared with the bases like sodium methoxide and the like.
The same reaction can be performed using cinnamic acid in place of cinnamic acid ester at temperatures up to 200°C and pressures of 100 psi, keeping the same stoichiometry (1 : 1.0 to 3). The excess diamine serves as solvent for the reaction.
The amidification reaction between a compound of Formula II when R5 = -C1 is carried out with that of Formula III at room temperature in the presence of solvent. The compounds of Formula IV are synthesised by reacting acid chlorides of Formula II (1.0 mole) when R5 is -C1 with the diamines of Formula III (1.0 to 1.2 mole) at 20 - 50°C in an inert solvent like dichloromethane, ethylene dichloride, tetrahydrofuran and the like.
The alkylating agent used in present invention is sodium 3-chloro-2-hydroxy propane sulphonate of Formula V that is in turn synthesised from epichlorohydrin and sodium bisulphite.
Quaternization of cinnamidoamines is carried out in solvents that include, water, lower alkanols, glycols and combinations thereof. Lower alkanols having one to four carbons atoms are suitable for use with the present invention. Glycols having from three to eight carbon atoms are suitable for use with the present invention. Mixtures of these solvents can also be used. Solvents used are from 20 to 80 % by weight of the reaction mass. The cinnamidoalkylamines (Formula IV, 1 mole) are N-alkylated with quatemising agents (Formula V, 1.0 mole) in the presence of suitable solvents preferably water, isopropanol that govern temperatures at which the reaction is carried out.
The quatemisation reaction can be conveniently done in a pressure reactor as well as in an open system. The temperatures suitable for pressure reaction range from about 60 - 125°C with the pressures up to 50 psi. The pressures are governed by the amount of solvent and the temperature selected for the reaction. The conditions of reaction in an open vessel also get dictated by the choice of solvent. The reactions are usually carried out at boiling point or slightly below boiling point of the solvent employed. The resulting betaines are obtained as concentrated solutions. The progress of the reaction is monitored by measuring unquatemized arrridoarnine or by estimation of
CI.
In another embodiment the process of the present invention relates to manufacture of compounds of Formula I, in which R1 is selected from H, -OH, -N02, -NH2, halogen, N,N-dialkylamino groups containing from 1 to 6 carbon atoms; R2 is selected from H, or is selected from alkyl groups containing from 1 to 12 carbon atoms, R3 and R4 are independently selected from alkyl groups containing from 1 to 12 carbon atoms, n is an integer having values from 1 to 6 from the compounds of Formula II, III, IV and V, with respective substituents R1 of Formula II, R2, R3, R4 and n of Formula III as defined for the compounds of Formula I in this embodiment and R5 of Formula II being -OH, -CI, -Br or -0(CH2)pCH3 (p = 0 to 3).
In another embodiment the process of the present invention relates to manufacture of compounds of Formula I, in which R1 is selected from H, -OH, halogen, NN-dialkylamino groups containing

from 1 to 6 carbon atoms, alkoxy groups containing from 1 to 6 carbon atoms; R2 is selected from alkyl groups containing from 1 to 12 carbon atoms, R3 = R4 = methyl; n = 3, from the compounds of Formula II, III, IV and V, with respective substituents R1 of Formula II, R2, R3, R4 and n of Formula III as defined for the compounds of Formula I in this embodiment and R5 of Formula II being -OH, -CI, -Br or -0(CH2)pCH3 (p = 0 to 3).
In another embodiment the process of the present invention relates to manufacture of compounds of Formula I, in which R1 = H; R2 is selected from H, alkyl group containing from 1 to 6 carbon atoms, R3 and R4 are independently selected from alkyl groups containing from 1 to 12 carbons, n is an integer between 1 and 6, from the compounds of general Formula II, HI, IV and V, with respective substituents Rt of Formula n, R2, R3, R4 and n of Formula III as defined for the compounds of Formula I in this embodiment and R5 of Formula II being -OH, -CI, -Br or -0(CH2)pCH3 (p = 0 to 3).
In another embodiment the process of the present invention relates to manufacture of a compound of Formula I, in which Ri = para -OCH3, R2 = -H, R3 = R* = -CH3 and n = 3, from the compounds of Formula II (p-methoxy ethyl cinnamate, R1 = -OCH3, R5 = -OC2H5), Formula III (N,N-dimethylpropyldiamine, R2 = -H, R3 = R4 = -CH3, n = 3) forming an intermediate compound of Formula IV (p-methoxy cinnamidopropyldimethyl amine, Ri = -OCH3, R2 = -H, R3 and R4 = -CH3) and Formula V (sodium 3-chloro-2-hydroxy propane sulphonate). The process of preparation of such compounds is given in Example I.
In another embodiment the process of the present invention relates to manufacture of a compound of Formula I, in which R1 = para -OCH3, R2 = -H, R3 = R4 = -CH3 and n = 3, from the compounds of Formula II (p-methoxy cinnamoyl chloride, R1 = OCH3, R5 = C1), Formula III (N,N-dimethylpropyldiamine, R2 = -H, R3 = R4 = -CH3, n = 3) forming an intermediate compound of Formula IV (p-methoxy cinnamidopropyldimethyl amine, R1 = -OCH3, R2 = -H, R3 and R4 = -CH3) and Formula V (sodium 3-chloro-2-hydroxy propane sulphonate). The process of preparation of such compounds is given in Example II.
In these sulphobetaines compounds as shown in Formula I, preferably the ring is unsubstituted (R1 is hydrogen) or contains one substituent more preferably in para position. R1 is selected from moieties such as -halo, -OH, -NH2, -N02, -OCH3, -N(CH3)2 on the phenyl ring.
Referring again to Formula I, the amido nitrogen is also preferably unsubstituted (R2 is hydrogen). However, the amido nitrogen may also contain a substituent, depicted in Formula I as R2, is selected from alkyl groups containing from 1 to 12 carbon atoms.
The quaternized nitrogen of compounds in accordance with the present invention contains three substituents, R3 and R4 as depicted in Formula I, R3 and R4 are preferably selected from benzyl and alkyl groups containing from 1 to 12 carbon atoms.
The compounds of the present invention are zwitterionic photofilters containing cinnamidoalkylamines moiety as shown in Formula I, in which n is an integer between 1 and 6,

both inclusive. Preferred zwitterionic photofilters in accordance with the present invention are compounds containing cinnamidoalkylamines in which n is 3.
Thus, the sulphobetaine photofilters of the present invention are formed by quatemising compounds of Formula IV by sodium 3-chloro-2-hydroxy propane sulphonate of Formula V. Given the quaternizing agent described above, the betaine type of compounds of the present invention of Formula I will contain a positively charged nitrogen and a negatively charged sulphonate group.
Examples
The invention will now be illustrated with the help of examples. The examples are by way of illustrations only and in no way restrict the scope of invention.
Example I
Epichlorohydrin was obtained from TamilNadu Petro Products, Chennai. ./V,./V-dimethyl propyldiamine and sodium sulphite were obtained from BASF and Thai Sulphate Ltd. respectively. Ethyl p/-methoxy cinnaniate was supplied by Galaxy Surfactants Ltd.
Process for preparation 3-(N-p-methoxy cinnamidopropyl. MTV-dimethyl ammonium)-2-hydroxy
propane-1-sulphonate:
The compound of Formula I, wherein, R1 = -OCH3; R2 = -H; R3 = R4 = CH3; n = 3.
p-Methoxy cinnamidopropyldimethylamine was synthesised from ethyl p-methoxy cinnaniate and N, N-dimethylpropyldiamine.
a) Preparation of p-methoxy cinnamidopropyldimethylamine :
Ethyl p-methoxy cinnaniate (206.0 g, 1.0 mole), NN-dimethylpropyldiamine (306.0 g, 3.0 mole) and sodium methoxide (2.0 g) were charged in a pressure reactor. The air inside the reactor was flushed out by purging of nitrogen. The reaction mixture was then- stirred at 180°C (this generated pressure of 18 kg / cm2) for 36 hours. The progress of reaction was monitored by disappearance of ethyl p-methoxy cinnaniate on chromatography (TLC and HPLC). The TLC was performed on aluminium coated silica gel plates (Merck - 60-F-254) and viewed with a UV lamp at 254 nm. HPLC was performed using reversed phase technique on a C-18 bonded (octadecyl silane) column and 60 % aqueous methanol as mobile phase (1.0 ml / min) and detection at 280 nm. The excess amine was removed under vacuum. The golden yellow solid (263.0 g) thus obtained had amine value of 245. Molar extinction coefficient, e, in methanol was found to be 24,224 at 290 nm.
IR in dichloromethane showed carbonyl stretching of amide at 1660 cm"1 and NH stretching at 3300 cm4.

H NMR (300 MHz, CDC13) : 5 1.73 (p, 2H, J = 6.6 Hz), 2.26 (s, 6H), 2.42 (t, 2H, J = 6.6 Hz), 3.45 (q, 2H, J = 6.0 Hz), 3.81 (s, 3H), 6.27 (d, 1H, J = 15.6 Hz), 6.86 (d, 2H, J = 8.7 Hz), 7.43 (d, 2H, J = 8.7 Hz), 7.53 (d, 1H, J = 15.6 Hz).
b) Preparation of sodium 3-chloro-2-hydroxy propane sulphonate :
To a stirred mixture of sodium bisulphite (294.0-g, 2.83 moles) and sodium sulphite (84.0 g, 0.67 moles) in water (514 ml), epichlorohydrin (250.0 g, 2.70 moles) was added dropwise maintaining the temperature of reaction mass below 20°C over a period of 6 hours. The reaction mass was cooled to 5°C and the precipitated white solid was filtered and dried at 100°C to yield 424.0 g (82 %) of sodium salt of 3-chloro-2-hydroxy propane sulphonic acid.
c) Preparation of 3-(.N-p-methoxy cinnamidopropyl. NN-dimethyl ammonium)-2-hydroxy
propane-1 -sulphonate :
p-Methoxy cinnamidopropyldimethyl amine (482.0 g, 1.84 moles) was charged in a stainless steel pressure reactor along with sodium 3-chloro-2-hydroxy propane sulphonate (397.0 g, 2.02 moles) and water (879 ml). The reaction mixture was stirred under nitrogen pressure of 0.5 kg / cm2 at 85 - 90°C. The reaction was monitored by estimation of either CI or unreacted cinnamidoalkylamine. The reaction was continued till the stoichiometric quantity of CI" was liberated to yield 1758 g of pale yellow coloured aqueous solution having solid content of 50.0 % andNaClof6.12%.
IR (KBr) : 1650 cm1, 3300 - 3400 cm1.
lH NMR (D20, 300 MHz) : 5 2.05 (m, 2H), 3.10 - 3.17 (m, 8H), 3.31 - 3.36 (t, 2H), 3.41 - 3.64 (m, 5H), 3.78 (s, 3H), 4.60 - 4.67 (m, 1H), 6.34 (d, 1H, J = 15 Hz), 6.91 (d, 2H, J = 9 Hz), 7.34 (d, 1H, J = 15 Hz), 7.45 (d, 2H, J = 9 Hz).
The molar extinction coefficient, E was found to be 24,000 at Amax 306 nm in water.
The final compound was analysed on HPLC using ion-pairing technique. The mobile phase employed for ion-pairing comprised of 0.1 M octane sulphonic acid in aqueous methanol (50 : 50). Reversed phase column Chromspher C8 was used with mobile phase flow rate of 0.5 ml / min. The detection was done at 280 nm. The retention time for 3-(N-p-methoxy cinnamidopropyl, N.N-dimethyl ammonium)-2-hydroxy propane-1-sulphonate was found to be 2.08 minutes.
The purity of final compound from this analysis was found to be 98.0 % with 2.0 % unquaternised
amine.
Example II
Process for preparation 3-(N-p-methoxy cinnamidopropyl. N,/N-dimethyl ammonium)-2-hydroxy
propane-1 -sulphonate :
The compound of Formula I, wherein, Ri = -OCH3; R2 = -H; R3 = R4 = CH3; n = 3.

p-Methoxy cinnamidopropyldimethylamine was synthesised from p-methoxy cinnamoyl chloride and N, N-dimethylpropyldiamine.
(a) Preparation of p-methoxy cinnamovl chloride :
To a stiiTed suspension of p-methoxy cinnamic acid (178.0 g, 1.0 mole) in dichloromethane (500 ml), thionyl chloride (238.0 g, 2.0 moles) was added slowly and the reaction mass was heated at 45°C for 3 hours. The excess of thionyl chloride was removed under vacuum and the p-methoxy cinnamoyl chloride was distilled (145°C / 0.2 mm) in 85 % yield as colourless solid with m. p. 50°C (Literature m.p. 50°C, Dictionary of Organic Compounds, Chapmann and Hall, 1994).
Co) Preparation of p-methoxy cinnamidopropyldimethylamine :
To a stirred solution of N, N-dimethylpropyldiamine (102.0 g, 1.0 mole) in dichloromethane (500 ml), solution of p-methoxy cinnamoyl chloride (196.0 g, 1.0 mole) in dichloromethane from step (a) was slowly added and the reaction was continued at room temperature for 2 hours. The reaction mixture in dichloromethane was washed with aqueous sodium hydroxide (200 ml, 20.0 %). The organic layer was dried over anhydrous sodium sulphate. The removal of solvent using a rotary evaporator afforded the p-methoxy cinnamidopropyldimethylamine (235.0 g) as colourless solid, m.p. 80°C. Reversed phase HPLC showed it to be 98 % pure with amine value 217.
The NMR, IR and HPLC data matched with the data for the compound obtained in Example I (b).
(c) Preparation of 3-C/V-p-methoxv cinnamidopropvl, N.^-dimethyl ammonium)-2-hydroxy
propane-1 -sulphonate :
The preparation was carried.out as per the experiment described in Example I (c).
The NMR, IR, UV data matched with the data obtained in Example I (c).
Example III
Process for preparation 3-(//-cinnamidopropyl. MA^-dimethyl ammoniumV2-hydroxy propane-1-
sulphonate :
The compound of Formula I, wherein, Ri = H; R2 = -H; R3 = R4 = CH3; n = 3.
Cirmamidopropyldimethylamine was synthesised from cinnamoyl' chloride and N,N-dimethylpropyldiamine.
(a) Preparation of cinnamidopropyldimethylamine :
To a stirred solution of A^A^-dimethylpropyldiamine (102.0 g, 1.0 mole) in dichloromethane (500 ml), solution of cinnamoyl chloride (166.5 g, 1.0 mole) in dichloromethane (500 ml) was slowly added and the reaction was continued at room temperature for 2 hours. The reaction mixture in dichloromethane was washed with aqueous sodium hydroxide (200 ml, 20.0 %). The organic layer was dried over anhydrous sodium sulphate. The removal of solvent using a rotary

evaporator afforded the ciimamidopropyldimethylamine (208.0 g) as colourless sticky solid with amine value of 228.
The molar extinction coefficient, e in methanol was found to be 23,000 at 280 nm.
IR (neat): 1665.0 cm"1 carbonyl of amide and 3320.0 cm"1 NH stretching.
*H NMR (300 MHz, CDC13) : 5 1.76 (p, 2H, J = 6.3 Hz), 2.28 (s, 6H), 2.47 (t, 2H, J = 6.6 Hz), 3.47 (q, 2H, J = 6.0 Hz), 6.40 (d, 1H, J = 15.9 Hz), 7.3 - 7.5 (m, 5H), 7.59 (d, 1H, J = 15.6 Hz).
(b) Preparation of 3-(N-cinnamidopropyl N, TV-dimethyl ammoniumV2-hydroxy propane-1-
sulphonate : Cinnamidopropyldimethyl amine (50.0 g, 0.21 moles) was charged in a stainless steel pressure reactor along with sodium 3-chloro-2-hydroxy propane sulphonate (42.0 g, 0.21 moles) and water (92 ml). The reaction mixture was stirred at 85 - 90°C. The reaction was monitored by estimation of either CI" or unreacted cinnamidoalkylamine. The reaction was continued till the stoichiometric quantity of CI" was liberated to yield 184 g of pale yellow coloured aqueous solution having solid content of 50.0 % and NaCl of 7.1 %.
IR (KBr): 1650 cm'1, 3300 - 3500 cm"1.
*H NMR (D20, 300 MHz) : 8 2.05 (m, 2H), 3.10 - 3.17 (m, 8H), 3.31 - 3.36 (t, 2H), 3.41 - 3.64 (m, 4H), 4.66 (m, 1H), 6.34 (d, 1H, J = 15 Hz), 7.41 - 7.6 (m, 6H).
The molar extinction coefficient, e was found to be 22,500 at Xmax 280 nm in water.
The final compound was analysed on HPLC using ion-pairing technique. The mobile phase employed for ion-pairing comprised of 0.1 M octane sulphonic acid in aqueous methanol (50 : 50). Reversed phase column Chromspher C8 was used with mobile phase flow rate of 0.5 ml / min. The detection was done at 280 nm. The retention time for 3-(/V-cinnamidopropyl, TV,TV-dimethyl ammonium)-2-hydroxy propane-1-sulphonate was found to be 2.1 minutes.
A process for preparing water-soluble, UV-absorbing sulphobetaines of general Formula I, from cinnamidoalkylamines and sodium 3-chloro-2-hydroxy propane sulphonate, substantially as herein described, in the text and in the examples.
The sulphobetaines prepared by the process of the present invention from cinnamidoalkylamines and sodium 3-chloro-2-hydroxy propane sulphonate of general Formula I, substantially as herein described, in the text and in the examples.

Advantages of the process :
The process of the present invention gives sulphobetaines having high solubility, substantivity and sunscreen properties useful in soaps and toiletries compositions and fabric care products. The process of the present invention gives a product in solution form and is convenient to use in the formulation directly.
The biggest advantage of the sulphobetaines of the present invention is that they are more substantive to hair when compared with water-soluble, cationic, UV-B absorbers of prior art especially when applied through a rinse-off preparation like shampoo that predominantly contains anionic surfactants.

We claim
1. A process for preparing UV-absorbing, water-soluble, 2-hydroxy sulphobetaines of cinnamidoalkylamines of Formula I,
Formula I


(CH2)n

wherein; R1 is a substituent, selected from -H, halo, -OH, -NH2, -NO2, -OCH3, -N(CH)3, alkyl groups containing from 1 to 6 carbon atoms, alkoxy groups containing from 1 to 6 carbon atoms, alkylamino or N,N-dialkylamino groups containing from 1 to 6 carbon atoms;
R2 is selected from hydrogen, alkyl group containing from 1 to 12 carbon atoms;
R3 and R4 are independently selected from benzyl, alkyl group containing from to 12 carbon atoms;
n is an integer from 1 to 6;
comprising steps of
i) reacting 1.0 mole of substituted cinnamic acid derivatives of Formula II, wherein, R1 is same as that in the compound of said Formula I, and R5 is , -OH, -CI, -0(CH2)pCH3 (p=0 to 3) or an alkyl group with 1 to 4 carbon atoms, with 1.0 to 3.0 moles of N.N-dialkyl diamines of Formula III, wherein, R2, R3, R4 and n are same as that for the compound of said Formula I, with or without solvent, with or without a basic catalyst, to obtain a compound of Formula IV, wherein, Ri, R2, R3, R4 and n are same as that for the compound of said Formula I till all of the compound of Formula II has been reacted;




Formula II

ii) carrying out quaternisation on compound of substituted cinnamido N.N-dialkyl amine of Formula IV obtained at the end of step (i) with 1.0 mole of sodium 3-chloro-2-hydroxy propane sulphonate compound of Formula V, by stirring under nitrogen, at about 85 to 100°C, in the presence of an water or other protic solvents from about 30 % to 80 % by weight of the reaction mass until CI" reaches the stoichiometric level to obtain compounds of Formula I.
Formula V

2. A process to synthesise compounds as claimed in claim 1, wherein the compounds of Formula IV are synthesised by reacting acid chlorides of Formula II (1.0 mole) when R5 is CI with the diamines of Formula III (1.0 to 1.2 mole) at 20 - 50°C in an inert solvent like dichloromethane, ethylene dichloride, tetrahydrofuran and the like.
3. A process as claimed in claim 1, step (i) wherein, the said reaction of compound of said Formula II when R5 is other than C1, with that of said Formula III is earned out at about 120°C to about 200°C, under pressure from about 10 psi to about 100 psi, in the presence of a basic catalyst such as sodium methoxide, sodium hydroxide, from 0.25 % to 5.0 % by weight of the reaction mass.
4. A process as claimed in claim 1, step (i), wherein, the said reaction of compound of said Formula II (1.0 mole) when R5 is other than C1, with that of said Formula III (1.0 to 1.2 mole) is earned out at about 120°C to about 200°C in the presence of basic catalyst such as sodium methoxide, sodium hydroxide from 0.25 % to 5.0 % by weight of the reaction mass under atmospheric pressure, under blanket of nitrogen, with an arrangement for continuous selective removal of lower alcohols formed in the reaction.
5. A process as claimed in claim 1, wherein, said reaction between intermediate compound of said Formula IV and that of said Formula V in step (ii) is carried out at the boiling point or slightly below the boiling point of any inert protic solvent like r-butanol, isopropanol, water and / or mixtures thereof in an open vessel.
6. A process as claimed in claim 1, wherein, the said solvent used in step (ii) is from about 20 % to 80 % by weight of reaction mass.
7. A process as claimed in any claim 1 - 6, wherein, compounds of Formula I are prepared, in which R1 is selected from -H, -OH, -N02, -NH2, halogen,N N-dialkylamino groups containing from 1 to 6 carbon atoms; R2 is selected from -H, or selected from alkyl groups containing from 1 to 12 carbon atoms, R3 and R4 are independently selected from alkyl groups containing from 1 to 12 carbon atoms and n is an integer having values from 1 to 6, from the compounds of Formula II, III, IV and V, with respective substituents R1 of Formula II, R2, R3, R4 and n of Formula III, as defined for the compounds of Formula I in this claim and R5 of Formula II being -OH, -CI, -Br or -0(CH2)pCH3 (p = 0 to 3).

8. A process as claimed in any claim 1-6, wherein, compounds of Formula I are prepared, in which R1 is selected from H, -OH, halogen, N,N-dialkylamino groups containing from 1 to 6 carbon atoms, alkoxy groups containing 1 to 6 carbon atoms; R2 is selected from alkyl groups containing from 1 to 12 carbon atoms, R3 = R4 = methyl and n = 3, from the compounds of Formula II, III, IV and V, with respective substituents R1 of Formula II, R2, R3, R4 and n of Formula III as defined for the compounds of Formula I in this claim and R5 of Formula II being -OH, -CI, -Br or -0(CH2)pCH3 (p = 0 to 3).
9. A process as claimed in any claim 1-6, wherein, compounds of Formula I are prepared, in which R1 = -H; R2 is selected from H, alkyl group containing from 1 to 12 carbon atoms, R3 and R4 are independently selected from alkyl groups containing from 1 to 12 carbon atoms and n is an integer between 1 and 6, from the compounds of general Formula II, III, IV and V, with respective substituents R1 of Formula II, R2, R3, R4 and n of Formula III as defined for the compounds of Formula I in this claim and R5 of Formula II being -OH, -C1, -Br or -0(CH2)pCH3 (p = 0 to 3).

10. A process as claimed in any claim 1 - 6, wherein, compounds of Formula I are prepared, in which R1 = para -OCH3, R2 = -H, R3 = R4 = -CH3 and n = 3, from the compounds of Formula II (p-methoxy ethyl cinnamate, Rt = -OCH3, R5 = -OC2H5), Formula III (N,N-dimethylpropyldiamine, R2 = -H, R3 = R4 = -CH3, n = 3) forming an intermediate compound of Formula IV (p-methoxy cinnamidopropyldimethyl amine, Rx = -OCH3, R2 = -H, R3 and R4 = -CH3), Formula V (sodium 3-chloro-2-hydroxy propane sulphonate)
11. A process as claimed in any claim 1-6, wherein, compounds of Formula I are prepared, in which R1 = para -OCH3, R2 = -H, R3 = R4 = -CH3 and n = 3, from the compounds of Formula II (p-methoxy cinnamoyl chloride, R1 = OCH3, R5 = CI), Formula III (N,N-dimethylpropyldiamine, R2 = -H, R3 = R4 = -CH3, n = 3) forming an intermediate compound of Formula IV (p-methoxy cinnamidopropyldimethyl amine, Ri = -OCH3, R2 = -H, R3 and R4 = -CH3), Formula V (sodium 3-chloro-2-hydroxy propane sulphonate).
12. A process for preparing water-soluble, UV-absorbing sulphobetaines of general Formula I, from cirmamidoalkylamines and sodium 3-chIoro-2-hydroxy propane sulphonate, substantially as herein described, in the text and in the examples.


Dated this 10 day of August, 2001

(Applicant)