Patents Covering the Formation of Amine Groups By Reduction

US patents found in class 564 subclass 375 on forming amine groups directly by reduction other than by reductive amination. Note: this is a 5 dot indent which covers compounds having an amino group on the second carbon atom of a side chain connected to a benzene ring. For more information see the Manual of Classification

1830705 NiCl --> Ni (on kieselguhr) using Al and NH₄Cl or Zn

2828343 lime + Cu sulfate --> catalyst for P2P and CH₃NH₂

2045574 Hydrogenation of ketimines, Ni catalyst

2146473 Methylation of phenylisopropylamine, 1) using methyl iodide on benzaldehyde Schiff base, and 2) using HCOH and activated Al

2146474 Para hydroxy P2P, alcohol, 40% aqueous CH₃NH₂, reduction using activated Al turnings

2146475 Para hydroxy P2P, NH₃, Ni catalyst 2-3 hours, 80º C, 20 atm

2204494 Para hydroxy P2P + C₆H₅NH₂ --> amine using activated Al turnings

2243295 Phenylpropanolamine and HCOH hydrogenated (Ni catalyst) to produce phenylisopropylmethylamine

2402626 Poison resistant metal sulfide catalysts

2414031 Nitromethane + aldehyde + PtO catalyst --> secondary amine

2636901 Raney Ni reduction of nitroolefins, (ie. phenylnitropropene) in the presence of an organic carboxylic acid

2647930 Raney Ni reduction of nitroolefins, (ie. phenylnitropropene) in the presence of an organic carboxylic acid

2700682 Ketimine reduction, example 1: P2P, CH₃NH₂, KOH drying agent, example 2: catalytic reduction using Pd/C

2768209 Hydrazine reduction of nitro compounds

2772311 Benzyl magnesium chloride + RCN intermediate reduced with lithium aluminum hydride to produce an amine

2828343 P2P + CH₃NH₂ reduction using cupric oxide catalyst

3084099 Benzaldehyde and nitropropane condensed to nitro intermediate which is reduced with zinc dust and acetic acid, also discloses HI/RP (yes, red phosphorus) process

3226442 Catalytic reduction of nitroolefins, gives reference to Ni on kieselguhr, etc.

3457354 Catalytic reduction of phenylnitropropenes, Ni on diatomaceous earth

3458576 Phenylnitropropenes reduced using Pd or Pt on Ni at low temperature and pressure (<100º C and <75 psig)

3541158 Phenylnitropropenes, inventor: Alexander Shulgin

3925475 P2P-like imines reduced with NaBH₄

4129598 Fe and HCl example for converting phenylnitropropenes to P2Ps

4307248 Ni catalysts and a lot of prior art patents

5360724 Organism with transaminase converts one enantiomer of phenylisopropylamine to P2P leaving the other enantiomer alone, the P2P can also be aminated to get more amine

5840989 doped Raney Ni

Also found in 564/374

1793176 2-methyl indole MgX (grignard reagent) reacted with ClCH₂CH₂N(CH₃)₂ to get 2-methyl DMT

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