FORM 2
THE PATENT ACT 1970
&
The Patents Rules, 2003
PROVISIONAL / COMPLETE SPECIFICATION (See section 10 and rule 13)
1. TITLE OF THE INVENTION A Novel process for preparation of N,N-bis-2,2,6,6- tetra methyl - 4 -piperidyl amines.
2. APPLICANT
(a) NAME : Sudarshan chemical Industries Ltd.
(b) NATIONALITY.: Indian Company, registered under the provisions of the
Companies Act, 1956
(c) ADDRESS : 162,WelIesley Road, Pune 411001.
Maharastra state, India..
3. PREAMBLE TO THE DESCRIPTION

PROVISIONAL
The following specifieation describes the invention,

COMPLETE
The following specification particularly describes the invention and the manner in which it is to be performed.

1

TITLE:
A novel process for preparation of N, N - bis - 2, 2, 6, 6 - tetra methyl - 4 -piperidyl amines.
TECHNICAL FIELD AND OBJECTIVE OF THE INVENTION
The present invention relates to a process for the preparation of N, N - bis -(2, 2, 6, 6 - tetra methyl - 4 - piperidyl) amines. More particularly, the present invention relates to a process for the preparation of N, N - bis - (2,2, 6,6 - tetra methyl - 4 - piperidyl) amines comprising single step reacting 2,2, 6, 6 - tetra methyl - 4 - piperidone with an amine in presence of Aluminum metal - Mercury chloride in organic polar solvents.
The main object of the present invention is to provide a novel process for the preparation of N, N - bis - 2,2, 6, 6 - tetra methyl - 4 - piperidyl amines. Another object of the present invention is to provide simple process under atmospheric pressure.
Still further object of the present invention is to provide method of producing N, N - bis - 2, 2, 6, 6 - tetra methyl - 4 - piperidyl amines with high purity and yield.
BACKGROUND AND PRIOR ART:
The 2,2, 6, 6 -tetra alkyl - 4 -piperidylamines are very useful compounds, such as N, N' - bis (2, 2,6,6- tetra methyl - 4 - piperidyl) hexamethylenediamine is being used to make ultraviolet stabilizers for polymeric materials. (Compare: patents US4086204 and EP0659750A1).
In prior art processes for the preparation of 2,2, 6, 6 -tetra alkyl - 4 -piperidylamine derivatives are disclosed in US patents nos. 4104248, 4326063, 4415688 and 4293466 wherein, platinum on carbon is used as catalyst for hydrogenating 2,2,6, 6 -tetra alkyl - 4 -piperidone in methanol or lower aliphatic alcohols under certain hydrogen pressure.
2

German patent No. 3,007,996 has described process, wherein a Raney lickel or cobalt catalyst is used in an inert organic solvent to produce jolyalkylpiperidylamines at low hydrogen pressures of between 5 and 30 bar (between about 72.5 and 435 psi).
Another process is disclosed in US4605743 wherein, 2, 2, 6, 6-tetraalkyl-4-piperidylamines are produced by reacting an amine with a 2, 2, 6, 6-tetraalkyl-4-piperidone in the presence of a palladium catalyst.
In this process reaction is performed at 60-80°C with about 100-750 psi hydrogen pressure in water or alcohols.
In above prior art methods, formation of 2, 2,6,6- tetra alkyl - 4 -piperidylamines in desired purity and yield is greatly depending on factors such as catalyst concentration, reaction temperature and reaction pressure. Also, metal catalysts such as palladium, platinum or Raney Nickel used in the prior art are pyrophoric in nature and are very much expensive
It has been now thought that the general method for formation of 2,2,6, 6 -tetra alkyl - 4 - piperidylamines can be further simplified by adopting new approach which is safer, easier to handle and overcomes the various disadvantages of the prior art procedures.
DEFICIENCIES OF PRIOR ART
1) The prior art processes involves use of very expensive catalyst such as palladium, platinum or Raney Nickel.
2) The process generally carried out under hydrogen pressure between 50-1000psi which involves great safety precaution
3) Since catalysts used in prior art processes are pyrophoric in nature, its handling, recovery, recycle and disposal involves considerable cautionary measures.
3

DESCRIPTION OF PRESENT INVENTION
The foregoing objects of the invention are accomplished and the problems and shortcomings associated with prior art techniques and approaches are overcome by the present invention as described bellow in the preferred embodiment.
The present invention relates to a process for preparation of 2,2, 6, 6 - tetra methyl - 4 - piperidylamines of formula (I),

(I)
wherein R is CI -CI8 alkyl, C5 -C6 cycloalkyl or C7 -C9 aralkyl; Rl, R2, R3 and R4 are same or different and are C1-C8 alkyl; A is H or C1-C8 alkyl and n is lor2 which process comprises reacting an amine of the formula R (NH2)n, wherein R and n are as defined above, with at least one 2,2,6, 6 -tetra alkyl - 4 - piperidone of the formula (II)

(II) wherein Rl, R2, R3 and R4 are as defined above; in the presence of a Aluminum metal and mercury chloride catalyst employing a reaction medium selected from the
4

group consisting of water, C1–C10 aliphatic alcohols, C2 -C6 aliphatic glycols and mixtures thereof.
According to present invention, the amines which may be employed are aromatic / aliphatic mono-and di- amino alkyl amines such as methylamine, butyl amine, dodecylamine, octadecylamine, triethylenediamine, tetraethylenediamine, hexamethylenediamine, and the like; arylamines such as aniline, phenylenediamine and the like; and aralkylamines such as benzylamine and the like. Preferred amine is hexamethylenediamine.
Suitable 4-piperidones which can be used in the process of this invention include 2,2, 6, 6 - tetramethyl-4-piperidone; 1,2,2, 6, 6 - pent methyl - 4 -piperidone; 1-ethyl - 2, 2, 6, 6 -tetramethyl-4-piperidone: l-n-octyl-2,2, 6, 6 -tetramethyl-4-piperidone; 2,6 -diethyl-2,6 -dimethyl-4-piperidone;and the like. The preferred 4-piperidone is 2, 2, 6, 6 -tetramethyl-4-piperidone.
The 2,2,6,6- tetra methyl - 4 - piperidylamines of formula (I) prepared in the present invention by reacting 2, 2,6, 6 -tetra alkyl - 4 - piperidone of the formula (II) with R(NH2)n in presence of Al-Hg catalyst in suitable organic polar solvents as shown below where R, R1,R2,R3, R4, A and n are as defined above.

\1
(ii)
(0
The Aluminum can be used in the form of a bulk metal or activated metal powder, turnings, foil, metal sheet forms, preferably in foil form along with very small amount mercuric chloride. Very little HgC12 is needed for complete amalgamation of the sheet's surface.
5

The suitable organic polar solvents used in present invention are substantially unreactive toward reactants, products and catalyst that include water, C1-C4 aliphatic alcohols, C2 -C6 aliphatic glycols and mixtures thereof. Preferred reaction media are water, methanol, ethanol, 2-propanol and mixtures of 2-propanol, ethanol and methanol with water.
The process of this invention is typically performed as follows. The amines, the 2,2, 6, 6 -tetraalkyl-4-piperidone, reaction medium and metal catalyst as mentioned are all charged to round bottom flask with reflux condenser.
The equivalent ratio of piperidone to amine function is preferably within the range of from 1:1 to 1.2:1.
The ratio of reagents to solvent is not critical, and typically solvent will comprise between about 5 to 10 volume of amines compound.
The process typically is carried out over a temperature range of about 40°-100°C, preferably 60°- 80°C. Pressure normally is not an important process condition and the process therefore normally is performed at ambient pressure or moderately elevated pressure generated in a sealed reactor if used, i.e., autogenously pressures
EXAMPLE
This invention is illustrated with the help of following example. Into a four neck round bottom flask equipped with mechanical stirrer and a condenser were charged 2-2.2 mole equivalent of 2,2, 6, 6 -tetramethyl-4-piperidone(TMP), 0.026 moles of C 1 ml-3ml methanol per millimole of HMDA and 2-5 mole equivalent of Aluminum foil and 0.3-3 mole% mercury chloride (HgC12) of HMDA under stirring. The exothermic reaction observed was controlled by external cooling and maintained temperature 40-60°C for 10-20 hours. The progress of reaction was monitored by Gas liquid Chromatography(GLC)., After
6

completion of the reaction, reaction mass was cooled to 25 °C-10°C and filtered through suction, washed with fresh methanol and concentrated the combined filtrate under reduced pressure to get off white crude solid, weighed 9-10gm(m.p.61-63°C) with 90 to 92 % of N,N'-bis(2,2,6,6tetramethyl-4-piperidyl) hexamethylenediamine by qualitative Gas liquid chromatography which can be purified by crystallization in acetone-water(l:l) to obtain 97% purity (Yield 70-75%).The product thus obtained was characterized by IR, NMR and GC-MS.
VARIATIONS
1) organic polar solvents used are substantially uncreative toward reactants, products and catalyst that include water, CI -C4 aliphatic alcohols, C2 -C6 aliphatic glycols and mixtures thereof. Preferred reaction media are water, methanol, ethanol, 2-propanol and mixtures of 2-propanol, ethanol and methanol with water.
2) Suitable 4-piperidones which can be used in the process of this invention include 2,2, 6, 6 - tetramethyl-4-piperidone; 1,2,2, 6, 6 - pent methyl - 4 -piperidone; 1-ethyl - 2,2, 6, 6 -tetramethyl-4-piperidone: l-n-octyl-2,2, 6,6-tetramethyl-4-piperidone; 2,6 -diethyl-2,6 -dimethyl-4-piperidone;and the like.
3) The amines which can be used are aromatic / aliphatic mono-and di- amino alkyl
amines such as methylamine, butyl amine, dodecylamine, octadecylamine,
triethylenediamine, tetraethylenediamine, hexamethylenediamine, and the like;
arylamines such as aniline, phenylenediamine and the like; and aralkylamines such
as benzylamine and the like.
Detailed descriptions of the preferred embodiment are provided herein; however, it is to be understood that the present invention may be embodied in various forms. Therefore, specific details disclosed herein are not to be interpreted as limiting, but rather as a basis for the claims and as a representative basis for
7

teaching one skilled in the art to employ the present invention in virtually any appropriately detailed system, structure or matter.
The embodiments of the invention as described above and the methods disclosed herein will suggest further modification and alterations to those skilled in the art. Such further modifications and alterations may be made without departing from the spirit and scope of the invention; which is defined by the scope of the following claims.
8

WE CLAIM
1) A novel process for preparation of N, N - bis - 2,2,6,6- tetra methyl - 4 -piperidyl amines of formula (I)



+ R-(NH2)n

(ID

(0

process comprises of reacting an amine of the formula R(NH2)n wherein R is selected from CI -CI8 alkyl, C5 -C6 cycloalkyl, C7 -C9 aralkyl; and n is a numerical; with 2,2,6, 6 -tetra alkyl - 4 - piperidone of formula (II) wherein R is selected from CI -CI8 alkyl, C5 -C6 cycloalkyl,C7 -C9 aralkyl; Rl, R2, R3 and R4 are selected from C1-C8 alkyl; A is selected from H and C1-C8 alkyl; n is a numerical; in the presence of, Aluminum metal and mercury chloride catalyst, and reaction medium; at a temperature range of 40°-100°C; for 10-20 hours; pressure is normally ambient pressure.
2) A novel process for preparation of N, N - bis - 2, 2,6,6 - tetra methyl - 4 -piperidyl amines of formula (I) as claimed in claim 1 wherein the reaction is performed using Aluminum metal in 2-5 mole equivalent and mercury chloride (HgC12) in 0.3-3 mole% of HMDA.
3) A novel process for preparation of N, N - bis - 2, 2, 6, 6 - tetra methyl - 4 piperidyl amines of formula (I) as claimed in claim 1 wherein said amine is
9

selected from the group consisting of methylamine, butyl amine, dodecylamine, octadecylamine, triethylenediamine, tetraethylenediamine, hexamethylenediamine, and the like; arylamines such as aniline, phenylenediamine and the like; and aralkylamines such as benzylamine and the like
4) A novel process for preparation of N, N - bis - 2,2, 6, 6 - tetra methyl - 4 -piperidyl amines of formula (I) as claimed in claim 1 wherein reaction medium ,is selected from the group consisting of water, CI -CIO aliphatic alcohols, C2 -C6 aliphatic glycols and mixtures thereof.
5) A novel process for preparation of N, N - bis - 2, 2, 6, 6 - tetra methyl - 4 -piperidyl amines of formula (I) as claimed in claim 1 wherein 4-piperidones used in the process of this invention are selected from group comprising of 2,2, 6, 6 -tetramethyl-4-piperidone; 1,2,2, 6,6 - pent methyl - 4 - piperidone; 1-ethyl - 2,2, 6, 6 -tetramethyl-4-piperidone: l-n-octyl-2,2, 6, 6 -tetramethyl-4-piperidone; 2,6 -diethyl-2,6 -dimethyl-4-piperidone;and the like.
6) A novel process for preparation of N, N - bis - 2,2, 6, 6 - tetra methyl - 4 -piperidyl amines of formula (I) as claimed in claim 1 substantially as herein described with reference to the example and specification.

CHETAN GUNDECHA (AGENT FOR THE APPLICANT)
Date 15th June 2007.
10

ABSTRACT
The present invention relates to a process for the preparation of N, N - bis - (2, 2, 6, 6 - tetra methyl - 4 - piperidyl) amines of formula (I) comprising of single step, reacting 2, 2, 6, 6 - tetra methyl - 4 - piperidone of formula (II) with an amine of the formula R(NH2)n in presence of Aluminum metal - Mercury chloride catalyst in organic polar solvent as reaction medium at ambient pressure.


R-(NH2)n

Ri
R2- NH
A- 'S ^
R3 \R4
-■n

-R

(II)

(I)