FIELD OF THE INVENTION:
A novel process for the preparation of Sutezolid and the present invention is also provides most economical and industrial applicable process.
BACKGROUND OF THE INVENTION:
Sutezolid (PNU-‐100480) is a synthetic antibiotic, the first of the oxazolidinone class, used for the treatment of extensively drug-resistant tuberculosis (TB) and other infectious diseases. However, sutezolid has better antimycobacterial activity than linezolid both in vitro and in a mouse model of TB. Sutezolid has an improved safety profile compared to linezolid and shows better time dependent killing in an ex vivo whole blood culture test. In addition, it has activity against both drug susceptible and drug resistant TB.
Sutezolid is chemically known as (S)-N-[[3-(3-fluoro-4-thiomorpholinylphenyl)-2-oxo-5-oxazolidinyl] methyl] acetamide having the formula (I).

Sutezolid is first disclosed in U.S. Pat. No. 5,880,118 and its process comprises the use of R–glycidylbutyrate which results in the formation of (R)-N-[[3-[3-fluoro-4-thiomorpholinyl] phenyl]-2-oxo-5-oxazolidinyl] methanol which in the subsequent stages has to be converted to various intermediary compounds to finally form Sutezolid, which is depicted in the scheme-I given below.

The above said prior art process, also encompasses an intermediary azide compound, which is difficult to handle at industrial level.
WO 2010/122456 A2 discloses a process for the preparation of Sutezolid, which is comprises compound of formula (XIV) reacted with the compound of formula (XIII) to get the (S)-1-chloro-3-[(4-chloro-E-benzylidene)-amino]-propan-2-ol of formula (XII), further it reacts with (3-fluoro-4-morpholin-4-yl-phenyl)-carbamic acid benzyl ester and followed by deprotection to obtained (S)-5-(aminomethyl)-3-(3-fluoro-4-thiomorpholinophenyl)oxazolidin-2-one dihydrochloride compound of formula (XVIIIa) and subsequently reacted with acetic anhydride to afford Sutezolid, which is depicted in the scheme-II given below:

In view of the above aforesaid methods available for Sutezolid, there is a need for simple and cost effective processes for the preparation of Sutezolid that provides improved efficiency per reaction volume in terms of yield and purity, including both chemically and chirally.
There is consequently a need for an alternative method for the preparation of Sutezolid and its intermediates, which does not involve the problems described above. Therefore, there is a need in the art for a simple and facile process for the synthesis of Sutezolid, and our inventors have developed a cost-effective and industrially viable process.
SUMMARY OF THE INVENTION
The present invention relates to a novel process for the preparation of sutezolid in terms of yield and purity, including both chemically and chirally.
In one aspect of the present invention relates to an novel process for the preparation of (S)-2-[3-(3-Fluoro-4-Thiomorpholin-4-yl-phenyl)-2-oxo-oxazolidin-5-ylmethyl]–iso

indole-1,3-dione of formula (XVII), which comprises reacting a carbamate compound of formula (XVI) with (S)-glycidylphthalimide of formula (IX) in the presence of base and organic solvent.

In another aspect of the present invention provides an novel process for the preparation of Sutezolid of formula (I) comprising the steps of:
a) reacting the compound of formula (XVI) with (S)-Glycidylphthalimide of formula (XVI) in the presence of base and organic solvent to give a compound of formula(XVII),
b) reacting the compound of formula(XVII) with aqueous methyl amine or hydrazine hydrate,
c) acylating the product of step b) with an acylating agent and
d) isolating the compound of formula (I).
The above synthetic process is illustrated by the following Scheme

In yet another aspect of the present invention provides a process for the preparation of methyl (3-fluoro-4-Thiomorpholinophenyl) carbamate (XVI) comprising 4-(2-fluoro-

4-nitrophenyl) thiomorpholine compound of formula (IX) on undergoes reduction and followed by reacted withalkyl halo formate in presence of base and organic solvent to obtain methyl (3-fluoro-4-Thiomorpholinophenyl) carbamate (XVI).

DETAILED DESCRIPTION OF THE INVENTION
The present invention relates to a novel process for the preparation of sutezolid. The present invention is also relates to commercially viable and industrially advantageous process for the preparation of Sutezolid and its intermediates.
An embodiment of the present invention provides an novel process for the preparation of (S)-2-[3-(3-Fluoro-4-Thiomorpholin-4-yl-phenyl)-2-oxo-oxazolidin-5-ylmethyl] -isoindole-1,3-dione of formula (XVII),which comprises reacting the carbamate compound of formula (XVI) with (S)-glycidylphthalimide of formula (XV) in the presence of organic solvent and base.

In an embodiment, the reaction is carried using organic base and in the presence of a solvent at a temperature in the range of 60° to 120 °C. The reaction is carried out for a period of 10 to 14 hours to get a desired compound of formula (XVII)
In an another embodiment of the present invention provides a novel process for the preparation of Sutezolid of formula (I) comprising the steps of;
a) reacting the compound of formula (XVI) with (S)-Glycidyl Phthalimide of
formula (XV) in the presence of organic solvent and base to give a compound
of formula (XVII),

b) reacting the compound of formula (XVII) with aqueous methyl amine or hydrazine hydrate,
c) acylating the product of step b) with an acylating agent and
d) isolating the compound of formula (I).
According to an embodiment of the present invention, the reaction between the compound of formula (XVI) with (S)-Glycidylphthalimide of formula (XV) is carried out in the presence of a suitable base and organic solvent at a suitable temperature, allow to stir and then raise the temperature at 60-80°C for 10-30 mins, preferably 70 to 75°C for 15-20 mins to obtain compound of formula (XVII); this compound is sub-jected to deprotection with hydrazine hydrae (or) aqueous methyl amine in presence of acidic conditions at 20-40°C under adjust pH to 9-12 (preferably at 25-30°C under pH 10-11) and stir for 15 minutes to get the residual product of (S)-5-aminomethyl-3-(3-fluoro-4-morpholin-4-yl-phenyl)-oxazolidin-2-one, which is subsequently acylated with acetic anhydride or acetyl chloride in presence of dichloromethane (MDC) at 20-25 C and allow to stir for 60 min to give (S)-N-[[3-(3-fluoro-4-thiomorpholinyl phenyl)-2-oxo-5-oxazolidinyl]methyl] acetamide (Sutezolid) of formula I.
In yet another embodiment of the present invention, provides a process for the pre-paration of methyl (3-fluoro-4-Thiomorpholinophenyl) carbamate (XVI) comprising, by reducing 4-(2-fluoro-4-nitrophenyl) thiomorpholine compound of formula (IX) with reducing agents in presence of organic solvent and further it is reacted with alkyl halo formate in presence of base and organic solvent to obtain methyl (3-fluoro-4-Thiomorpholinophenyl) carbamate (XVI).
According to an embodiment of the present invention, reducing agent is selected from Palladium carbon (Pd/C), sodiumborohydride, raney.Nickel, lithium aluminum hydride, stannic chloride, Iron powder, Diisobutylaluminum hydride, Diborane Sodium amalgam.
According to an embodiment of the present invention, the esterification is carried out in the presence of the alkyl halo formate is selected from methylchloro formate, ethylchloro formate, propylchloro formate and butylchloro formate. Preferably methylchloro formate

According to an embodiments of the present invention, the suitable bases are selected from organic bases such as methyl amine, dimethyl amine, trimethyl amine, diisopropyl ethyl amine; inorganic bases such as sodium carbonate, potassium carbonate, calcium carbonate and lithium carbonate.
According to an embodiments of the present invention, the suitable organic solvents are selected from alcohols such as methanol, ethanol, isopropyl alcohol and the like or mixture thereof; ketones such as methyl isobutyl ketone, methyl ethyl ketone, n-butanone and the like; halogenated solvents such as dichloromethane, ethylene dichloride, chloroform and the like; esters such as ethyl acetate, n-propyl acetate, isopropyl acetate and the like; hydrocarbon solvents such as toluene, xylene, cyclohexane and the like; ethers such as 1,4-dioxane, tetrahydrofuran and the like; and amides such as N,N- dimethylformamide, Ν,Ν-dimethylacetamide and the like or dimethylsulfoxide or mixture of solvents thereof.
According to an embodiment of the present invention, the acylation is carried out in the presence of acetic anhydride or acetyl chloride.
Advantages of the present invention:
1. The present invention is a simple, operation friendly and industrially
applicable process.
2. The process is commercially viable and provides the compounds in high yield,
which makes the process cost effective.
3. The reaction sequence of the present invention is carried out in a shorter time
span with high purity and less impurity profile.
The process details of the invention are provided in the examples given below, which are provided by way of illustration only and therefore should not be construed to limit the scope of the invention.

Experimental procedure:
Example: - 1:
Preparation of methyl (3-fluoro-4- thiomorpholine phenyl) carbamate
A mixture of 4-(2-fluoro-4-nitrophenyl) thiomorpholine(140 gm,0.577moles) in ethyl acetate (700ml) and Zinc dust ( 70.0 gm,1.07moles) in a R.B flask at 20- 30°C , raise the mixture temperature to reflux, slowly added ammonium chloride aqueous solution (60gm,1.12 moles) over a period of 1-2 hrs and maintain the mixture till completion of the reaction (~2-4 hrs) at reflux condition. The reaction mixture was cooled to 25-30°C and filtered through hyflo bed and wash with ethyl acetate (100ml). The resultant ethyl acetate layer was taken into the flask, followed by purified water (1000ml), sodium carbonate (100gm, 1.20 moles) and stir at 25-30°C. The reaction mixture was allow to cool at 0-5°C and slowly add methylchloroformate (70 gm, 0.740 moles) at below 10°C over a period of 30-60 min. and maintain till completion of the reaction, separate two layers,the obtain organic layer solvent (ethyl acetate) was distilled out under reduced pressure at below 50°C to get an residue and further it was isolated with toluene (200 ml). The obtain solid was filtered, washed with purified water (140ml) and dried at 60-70°C to afford a pure methyl (3-fluoro-4-thiomorpholine phenyl)carbamate. Yield :140gm (90%).
Example: - 2
Preparation of methyl (3-fluoro-4-thiomorpholine phenyl) carbamate
A mixture of 4-(2-fluoro-4-nitrophenyl)thiomorpholine (140 gm,0.577moles) in methanol (500ml) and iron powder (70.0 gm,1.25 moles) in a R.B flask at 20- 30°C, raise the mixture temperature to reflux, slowly added acetic acid (55gm,0.91 moles) over a period of 1-2 hrs and maintain the mixture till completion of the reaction (~4-6 hrs) at reflux condition. The reaction mixture was cooled to 25-30°C and filtered through hyflo bed and wash with methanol (100ml). The resultant methanol layer was taken into the flask, followed by purified water (100 ml), sodium carbonate (100gm, 1.20 moles) and stir at 25-30°C. The reaction mixture was allow to cool at 0-5°C and slowly add methylchloroformate (70gm., 0.740 moles) at below 10°C over a period of 30-60 min and maintain till completion of the reaction. The obtain precipitate solid

was filtered and washed with purified water (140ml ), dried at 60-70°C, to obtained a pure methyl (3-fluoro-4- thiomorpholine phenyl) carbamate. Yield :135gm ( 86%).
Example: - 3
Preparation of methyl (3-fluoro-4- thiomorpholine phenyl) carbamate
A mixture of 4-(2-fluoro-4-nitrophenyl) thiomorpholine (140 gm,0.577moles) in ethyl acetate (700ml) and 5%palladium charcoal ( 7.0 gm) charge in an autoclave and feed hydrogen gas 3.0-5.0 kg pressure at 20-30°C, and maintain the mixture under hydrogen pressure till completion of the reaction (~10-12 hrs). the reaction mixture was filtered through hyflo bed under nitrogen atmosphere and wash with ethyl acetate. The resultant ethyl acetate layer taken into the flask , followed by purified water (1000ml) and sodium carbonate (100gm,1.20 moles) and stir at 25-30°C. The reaction mixture was allow to cool at 0-5°C and slowly add ethylchloroformate (70gm, 0.645moles) at below 10°C over a period of 30-60 min , and maintain till completion of the reaction. The obtain precipitate solid was filtered and washed with purified water (140ml ), dry the solid at 60-70°C, to obtained pure Ethyl (3-fluoro-4-thiomorpholine phenyl) carbamate. Yield: 140.0 gm (90%).
Example-4:
Preparation of (S)-2-[3-(3-fluoro-4-thiomorpholin-4-yl-phenyl)-2-oxo-oxazolidin-5-ylmethyl]-isoindole-1,3-dione
Methyl (3-fluoro-4-thiomorpholinophenyl) carbamate (50 g, 0.185 moles) were added in ethyl acetate (100 ml) and stirred for 10 min at 25 to 30 °C, followed by one lot addition of [(2S)-oxiran-2-ylmethyl]-1H-isoindole-1,3(2H)-dione (50 g, 0.246 moles) and triethyl amine (5ml) at same temperature, slowly raised to 70-75 °C and maintained for about 6-8 hrs till complies the reaction, checked by Thin layer chromatography (TLC). The reaction mixture was cooled to room temperature and allow to stir at 25-30°C for 30 min. The obtain precipitated solid was filtered and washed with ethyl acetate (100 ml) to get desired compound and further it was

recrystallized with ethyl acetate to afford a pure (5S)2-[3-(3-fluoro-4-morpholin-4-yl-phenyl)-2-oxo-oxazolidin-isoindole-1,3-dione. Yield: 70 g (85% yields on theoretical)
Example-5:
Preparation of (S)-2-[3-(3-fluoro-4-thiomorpholin-4-yl-phenyl)-2-oxo-oxazolidin-5-ylmethyl]-isoindole-1,3-dione
Methyl (3-fluoro-4-thiomorpholinophenyl) carbamate (50 g, 0.196 moles) were added in dimethyl formamide (75 ml) and stirred for 10 min at 25 to 30 °C, followed by one lot addition of 2-[(2S)-oxiran-2-ylmethyl]-1H-isoindole-1,3(2H)-dione (50g,0.246 moles) and triethyl amine (3 ml) at same temperature, slowly raised to 70-75 °C and maintained for about 4-6 hrs till complies the reaction, checked by TLC. The reaction mixture was cooled to room temperature and allow to stir at 25-30°C for 30 min. The obtain precipitated solid was filtered and washed with methanol (50 ml) to get desired compound and further it was recrystallized with ethyl acetate to afford a pure (5S)2-[3-(3-fluoro-4-morpholin-4-yl-phenyl)-2-oxo-oxazolidin-isoindole-1,3-dione. Yield: 60 g (73.5%)
Example-6:
Preparation of (S)-2-[3-(3-fluoro-4-thiomorpholin-4-yl-phenyl)-2-oxo-oxazolidin-5-ylmethyl]-isoindole-1,3-dione
Methyl (3-fluoro-4-thiomorpholinophenyl) carbamate (50 g, 0.185moles) were added in dimethyl sulphoxide (65ml) and stirred for 10 min at 25 to 30 °C, followed by one lot addition of 2-[(2S)-oxiran-2-ylmethyl]-1H-isoindole-1,3(2H)-dione (50g,0.246 moles) and triethyl amine (7ml) at same temperature, slowly raised to 70-75 °C and maintained for about 4-6 hrs till complies the reaction, checked by TLC. The reaction mixture was cooled to ambient temperature and allow to stir at 25-30°C for 30 min. The obtain precipitated solid was filtered and washed with methanol (50 ml) to get desired compound and further it was recrystallized with ethyl acetate to afford a pure (5S)2-[3-(3-fluoro-4-morpholin-4-yl-phenyl)-2-oxo-oxazolidin-isoindole-1,3-dione. Yield: 58 g (71.0%)

Example- 7:
Preparation of (S) 2-[3-(3-fluoro-4-thiomorpholin-4-yl-phenyl)-2-oxo-oxazolidin-5-ylmethyl]-isoindole-1,3-dione
Methyl (3-fluoro-4-thiomorpholinophenyl) carbamate (25g,0.0925moles) were added in n-butanol (50 ml) and stirred for 10 min at 25 to 30 °C, followed by one lot addition of 2-[(2S)-oxiran-2-ylmethyl]-1H-isoindole-1,3(2H)-dione (25 g,0.123moles) and triethyl amine (4ml) at same temperature, slowly raised to 85-90 °C and maintained for about 20-24 hrs till complies the reaction, checked by TLC. The reaction mixture was cooled to ambient temperature and allow to stir at 25-30°C for 30 min. The obtain precipitated solid was filtered and washed with ethyl acetate (50 ml) to get desired compound and further it was recrystallized with ethyl acetate to afford a pure (5S)2-[3-(3-fluoro-4-morpholin-4-yl-phenyl)-2-oxo-oxazolidin-isoindo le-1,3-dione. Yield: 29 g (71%)
Example- 8:
Preparation of (S) 2-[3-(3-fluoro-4-thiomorpholin-4-yl-phenyl)-2-oxo-oxazolidin-5-ylmethyl]-isoindole-1,3-dione
To a mixture of methyl-(3-fluoro-4-morpholinophenyl) carbamate (20g,0.0784 moles), 2-[(2S)-oxiran-2-ylmethyl]-1H-isoindole-1,3(2H)-dione (20g,0.0984 moles) in dime¬thyl formamide (80 ml) followed by one lot addition of sodium iodide (4.0 g) at 25 to 30 °C, slowly raised to 110-115 °C and maintained for about 20-24 hrs till complies the reaction, checked by TLC. The reaction mixture was cooled to ambient temperature and allow to stir at 25-30°C for 30 min. The obtain precipitated solid was filtered and washed with water (20 ml) to get desired compound and further it was recrystallized with methanol (20 ml) to afford a pure (5S)2-[3-(3-fluoro-4-morpholin-4-yl-phenyl)-2-oxo-oxazolidin-isoindole-1,3-dione. Yield: 25 g (76%)
Example- 9:
Preparation of (S) 2-[3-(3-fluoro-4-thiomorpholin-4-yl-phenyl)-2-oxo-oxazolidin-5-ylmethyl]-isoindole-1,3-dione

Methyl (3-fluoro-4-thiomorpholinophenyl)carbamate (50 g,0.185 moles) were added in ethyl acetate (100 ml) and stirred for 10 min at 25 to 30 °C, followed by one lot addition of 2-[(2S)-oxiran-2-ylmethyl]-1H-isoindole-1,3(2H)-dione (50g,0.246 moles) and lithium tertiary butoxide (5.0 g,0.0624 moles) at same temperature, slowly raised to 70-75 °C and maintained for about 6-8 hrs till complies the reaction, checked by TLC. The reaction mixture was cooled to ambient temperature and allow to stir at 25-30°C for 30 min. The obtain precipitated solid was filtered and washed with ethyl acetate (50 ml) to get desired compound and further it was recrystallized with ethyl acetate to afford a pure (5S)2-[3-(3-fluoro-4-morpholin-4-yl-phenyl)-2-oxo-oxazoli din-isoindole-1,3-dione. Yield: 70 g (85% yields on theoretical)
Example- 10:
Preparation of (S) 2-[3-(3-fluoro-4-thiomorpholin-4-yl-phenyl)-2-oxo-oxazolidin-5-ylmethyl]-isoindole-1,3-dione
Methyl (3-fluoro-4-thiomorpholinophenyl) carbamate (25g,0.0925moles) were added in tetrahydrofuran (50 ml), 2-[(2S)-oxiran-2-ylmethyl]-1H-isoindole-1,3(2H)-dione (25 g,0.123 moles) and stirred for 10 min at 25 to 30 °C, followed by one lot addition of sodium hydride (1.2 gm,0.05 moles) at same temperature, slowly raised to 50-60 °C and maintained for about 2-3 hrs till complies the reaction, checked by TLC. The reaction mixture was cooled to ambient temperature and allow to stir at 25-30°C for 30 min. The obtain precipitated solid was filtered and washed with ethyl acetate (125 ml) to get desired compound and further it was recrystallized with ethyl acetate to afford a pure (5S)2-[3-(3-fluoro-4-morpholin-4-yl-phenyl)-2-oxo-oxazolidin-isoind ole-1,3-dione. Yield: 34 g (83%)
Example-11:
Preparation of N-({(5S)-3-[3-fluoro-4-(thiomorpholin-4-yl) phenyl]-2-oxo-1,3-oxazolidin-5-yl} methyl) acetamide (Sutezolid)

To a mixture of methanol (100 ml), DM water (400 ml), (S)-2-[3-(3-fluoro-4-thiomorpholin-4-yl-phenyl)-2-oxo-oxazolidin-5-ylmethyl]-isoindole-1,3-dione (100 g, 0.226 moles) and methyl amine solution (50 g) was added at a temperature of 25-30 °C. The reaction mixture was allow to stir at 80-85 °C and maintained for 2-3 hours, till completion of reaction. The reaction mixture was cooled to 25-30 °C, added MDC (500 ml), stir for 15 min, separated the layers. The obtain MDC layer was distilled out completely under atmospheric pressure to get the residual product of formula (XVIII), MDC was added (400 ml) to the residue and followed by slowly addition of acetic anhydride (25 g) at 25-30°C over a period of 60 min. After completion of reaction (Checked by TLC), 5% aqueous sodium bicarbonate solution was slowly added to the reaction mixture and stir 15 minutes to separate layers. The resultant MDC layer was washed with DM Water (200 ml) and obtained MDC layer was filtered through hyflo bed and the filtrate solvent was distilled off completely under vacuum at below 40°C to get a residue.
Cyclohexane (500 ml) was added to the residue and heated to 45-50°C. The obtained slurry was cooled to 20-25°C and stirred for 60 min at same temperature. The resultant solid was filtered, washed with cyclohexane (200 ml) and dried at 45-55°C to furnish pure crystalline solid of N-({(5S)-3-[3-fluoro-4-(thiomorpholin-4-yl)phenyl]-2-oxo-1,3-oxazolidin-5-yl}methyl)acetamide (Sutezolid). Yield: (53 g, 66% ).
Example-12:
Preparation of N-({(5S)-3-[3-fluoro-4-(thiomorpholin-4-yl) phenyl]-2-oxo-1, 3-oxazolidin-5-yl} methyl) acetamide (Sutezolid)
To a mixture of methanol (100 ml), DM water (400 ml) and (S)-2-[3-(3-fluoro-4-thiomorpholin-4-yl-phenyl)-2-oxo-oxazolidin-5-ylmethyl]-isoindole-1,3-dione (100 g, 0.226 moles) hydrazine hydrate aqueous solution (50 g) was added at a temperature of 25-30 °C. The reaction mixture was allow to stir at 80-85 °C and maintained for 2-3 hours. The reaction mixture was cooled to 25-30 °C and MDC (500 ml) was added. The reaction mixture was stirred for 15 min, separated the layers. The obtain MDC layer was distilled out completely under atmospheric pressure to get the residual product of formula (XVIII). MDC was added (400 ml) to the residue and followed by slowly addition of acetic anhydride (25 g) at 25-30 °C over a period of 60 min. After

completion of the reaction (checked by TLC), 5% aqueous sodium bicarbonate solution was slowly added to the reaction mixture, and stir for 15 min to separate layers. The resultant MDC layer was washed with water (200 ml) and obtained MDC layer was filtered through hyflo bed and the filtrate solvent was distilled off completely under vacuum at below 40 °C to get a residue.
Methanol (500 ml) was added to the residue and heated to 45-50 °C. The obtained slurry was cooled to 20-25°C and stirred for 60 min at same temperature. The resultant solid was filtered, washed with methanol (200 ml) and dried at 45-55°C to furnish pure crystalline solid of N-({(5S)-3-[3-fluoro-4-(thiomorpholin-4-yl)phenyl]-2-oxo-1,3-oxazolidin-5-yl}methyl)acetamide (Sutezolid). Yield: (53 g, 66%)

We Claims:
1. A process for the preparation of (S)-N-[[3-[3-fluoro-4-[4-thiomorpholinyl]
phenyl]-2-oxo-5-oxazolidinyl]methyl]phthalimide of formula (XVII), which
comprises the steps of reacting the carbamate compound of formula
(XVI)with (S)-glycidylphthalimide of formula (XV) in the presence
of organic solvent and base.

(I)
a) reacting the compound of formula (XVI) with (S)-Glycidyl Phthalimide of
formula (XV) in the presence of organic solvent and base to give a compound of formula (XVII),
b) reacting the compound of formula (XVII) with aqueous methyl amine or
hydrazine hydrate,
c) acylating the product of step b) with an acylating agent and
d) isolating the compound of formula (I).
3. The process as claimed in claim 2, the acylating reagent is selected from acetic
anhydride or acetyl chloride.
4. A process for the preparation of methyl (3-fluoro-4-Thiomorpholinophenyl)
carbamate (XVI) comprising, 4-(2-fluoro-4-nitrophenyl) thiomorpholine
compound of formula (IX) on undergoes reduction and followed by reacted

with alkyl halo formate in presence of base and organic solvent to obtain methyl (3-fluoro-4-Thiomorpholinophenyl) carbamate (XVI).

The process as claimed in claim 4, the alkyl halo formate is selected from the group consisting of methylchloro formate, ethylchloro formate, propylchloro formate and butylchloro formate, preferably methylchloro formate.
The process as claimed in claim 4, reducing agent is selected from the group consisting of Palladium carbon (Pd/C), sodiumborohydride, Raney.Nickel, lithium aluminum hydride, stannic chloride, Iron powder, Diisobutylaluminum hydride, Diborane Sodium amalgam.
. The process as claimed in preceding claims wherein the base is selected from the group consisting of triethyl amine, diisopropyl ethylamine, sodium carbonate, potassium carbonate and lithium carbonate.
. The process as claimed in preceding claims wherein the solvent is selected from the group consisting of ethyl acetate, dimethyl formamide, methanol, ethanol, isopropyl alcohol, dichloromethane and dimethyl sulfoxide or mixtures thereof.