Classifications

• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07D—HETEROCYCLIC COMPOUNDS
  • C07D295/00—Heterocyclic compounds containing polymethylene-imine rings with at least five ring members, 3-azabicyclo [3.2.2] nonane, piperazine, morpholine or thiomorpholine rings, having only hydrogen atoms directly attached to the ring carbon atoms
  • C07D295/02—Heterocyclic compounds containing polymethylene-imine rings with at least five ring members, 3-azabicyclo [3.2.2] nonane, piperazine, morpholine or thiomorpholine rings, having only hydrogen atoms directly attached to the ring carbon atoms containing only hydrogen and carbon atoms in addition to the ring hetero elements
  • C07D295/027—Heterocyclic compounds containing polymethylene-imine rings with at least five ring members, 3-azabicyclo [3.2.2] nonane, piperazine, morpholine or thiomorpholine rings, having only hydrogen atoms directly attached to the ring carbon atoms containing only hydrogen and carbon atoms in addition to the ring hetero elements containing only one hetero ring
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07D—HETEROCYCLIC COMPOUNDS
  • C07D295/00—Heterocyclic compounds containing polymethylene-imine rings with at least five ring members, 3-azabicyclo [3.2.2] nonane, piperazine, morpholine or thiomorpholine rings, having only hydrogen atoms directly attached to the ring carbon atoms
  • C07D295/02—Heterocyclic compounds containing polymethylene-imine rings with at least five ring members, 3-azabicyclo [3.2.2] nonane, piperazine, morpholine or thiomorpholine rings, having only hydrogen atoms directly attached to the ring carbon atoms containing only hydrogen and carbon atoms in addition to the ring hetero elements
  • C07D295/023—Preparation; Separation; Stabilisation; Use of additives

Definitions

• the present invention relates to a process for the preparation of piperidine.
• piperidine can be prepared quite economically according to the process of the present invention, whereby 4-cyanobutyraldehyde is hydrogenated in the presence of a hydrogenation catalyst and ammonia.
• the 4-cyanobutyraldehyde starting material for this process may be prepared in a suitable maner from relatively inexpensive basic materials such as acetaldehyde and acrylonitrile by a process, for example, according to application U.S. Ser. No. 8,704 filed Feb. 4, 1970 by the present applicants.
• the amount of ammonia required in practicing the present invention is not critical, and may be varied over a wide range. A favorable influence on the yield can be noticed at an ammonia to 4-cyanobutyraldehyde molar ratio as low as about 2:1. For optimum results, however, it is preferable to use an ammonia to 4-cyanobutyraldehyde molar ratio within a range from about 5:1 to 25:1.
• various known and typical hydrogenation catalysts may be employed, such as nickel or cobalt on a carrier or in the form of a Raney-catalyst and catalysts containing a platinum-metal such as platinum and palladium.
• the present process can be carried out with or without an inert solvent.
• suitable solvents include water, lower alkanols such as methanol, ethanol and isopropanol, and lower alkyl ethers, or mixtures of any of the above.
• the present process is preferably carried out at a temperature in the range of between about 50 C. up to about 200 C., but most preferably at a temperature of about 80 to 150 C.
• a pressure in the range from about -1 to 300 atmospheres may be used but a pressure of 25 to 125 atmospheres is preferable.
• the resulting reaction product obtained by the present process consists primarily of piperidine. There may also be some by-product formation of 1,5-diaminopentane, but this is not objectionable in that 1,5-diaminopentane can be recovered and easily converted to piperidine, for example by a process as disclosed in Chemische Berichte, volume 95, 1962, page 1992.
• the process of the present invention can be carried out either continuously or as a batch process by any of a number of known hydrogenation methods.
• a batch process it is preferably carried out by adding the 4- cyanobutyraldehyde to the ammonia-catalyst mixture whilethe latter is kept under hydrogen pressure. In this way, the'by-product formation of 1,5-diaminopentane is minimized.
• EXAMPLE 1 Methanol (250 ml.) and ammonia (425 g., 25 moles) were introduced into a 5 l. autoclave provided with a stirrer and a feed line, along with a Raney nickel catalyst (30 g.). The ammonia was introduced by connecting the autoclave with a bomb containing liquid ammonia. Hydrogen was fed into the autoclave until a pressure of 55 atmospheres was reached whereupon this mixture in the autoclave was heated to 125 C. A solution of 4-cyanobutyraldehyde (121.3 g., 1.25 moles) in methanol (750 ml.) was then added to the autoclave with simultaneous stirring over a period of 1.5 hours while maintaining the mixture temperature at 125 C.
• EXAMPLE 2 Methanol (350 ml.) and ammonia (170 g., 10 moles) were introduced into a 5 l. autoclave provided with a stirrer and fed line, along with a Raney nickel catalyst (40 g.). Hydrogen was fed into the autoclave until a pressure of 80 atmospheres Wes reached whereupon the mixture in the autoclave was heated to 120 C. A solution of 4- cyanobutyraldehyde (121.3 g., 1.25 moles) in methanol (750 ml.) was then added to the autoclave with simultaneous stirring over a period of 2 hours while maintaining the mixture temperature at 120 C. An additional ml. of methanol was fed to the autoclave in order to wash out the feed line.
• EXAMPLE 3 Methanol (400 ml.) and ammonia (380 g., 22.5 moles) were introduced into a l. autoclave provided with a stirrer and feed line, along with a Raney nickel catalyst (30 g.). Hydrogen was fed into the autoclave until a pressure of 115 atmospheres was reached whereupon this mixture in the autoclave was heated to 95 C. A solution of 4-cyanobutyraidehyde (120 g. of impure 4-cyanobutyraldehyde, equivalent to 1.16 moles of pure 4-cyan'obutyraldehyde) in methanol (700 ml.) was then added to the autoclave with simultaneous stirring over a period of 2 hours while maintaining the mixture at temperature of 95 C.
• 4-cyanobutyraidehyde 120 g. of impure 4-cyanobutyraldehyde, equivalent to 1.16 moles of pure 4-cyan'obutyraldehyde
• EXAMPLE 4 4-cyanobutyraldehyde (121.3 g., 1.25 moles) dissolved in methanol (750 ml.), and ammonia (425 g., 25 moles) were fed into a 5 l. autoclave provided with a stirrer and feed line, along with a Raney nickel catalyst (40 g.). Hydrogen was fed into the autoclave until a pressure of 60 atmospheres was reached. The mixture in the autoclave was then heated to 105 C. with simultaneous stirring over a period of 1 hour and thereafter maintained at this temperature for an additional hour with continuous stirring. The mixture was then cooled to room temperature. The autoclave was opened, the catalyst recovered by filtration, and the filtrate was dried with sodium sulphate.
• the dried filtrate was then distilled to recover the methanol, and the remaining product contained 73.3 g. of piperidine (0.86 mole) having a boiling point of 103-1104 C. and 30.6 g. of 1,5-diaminopentane (0.3 mole) having a boiling point of 174-177" C.
• the yield calculated on the basis of A-cyanobutyraldehyde was 69% for the piperidine, and 24%. for the 1,5-diaminopentane.
• a process for the preparation of piperidine consisting essentially in the hydrogenation of 4-cyanobutyraldehyde in the presence of a hydrogenation catalyst and ammonia wherein said hydrogenation is carried out at a temperature of between and 200 C. and at a pressure of between 1 and 300 atmospheres.

Landscapes

• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Hydrogenated Pyridines (AREA)
• Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
• Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=26644418

Family Applications (1)

Country Status (7)

Cited By (4)

Families Citing this family (1)

• 1969
  • 1969-03-29 NL NL6904908A patent/NL6904908A/xx unknown
• 1970
  • 1970-03-24 GB GB04339/70A patent/GB1243327A/en not_active Expired
  • 1970-03-26 CH CH463270A patent/CH531514A/de not_active IP Right Cessation
  • 1970-03-26 DE DE19702014837 patent/DE2014837A1/de active Pending
  • 1970-03-27 BE BE748143D patent/BE748143A/fr unknown
  • 1970-03-27 FR FR7011196A patent/FR2040098A5/fr not_active Expired
  • 1970-03-30 US US23981A patent/US3658824A/en not_active Expired - Lifetime

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