129757-63-7

Upstream product

• 663600-32-6 1-phenethyl-pentylamine 
• 99-33-2 3,5-dinitrobenoyl chloride 
• 127221-99-2 (2S,3''R)-1-[N-(1-butyl-3-phenylpropyl)-N-methoxycarbonylamino]-2-(2-methoxy ethoxymethyl)pyrrolidine 
• 129757-50-2 N-((S)-2,2-Dimethyl-1-phenethyl-propyl)-N-[(S)-2-(2-methoxy-ethoxymethyl)-pyrrolidin-1-yl]-acetamide 
• 129757-54-6 (R)-N-(methoxycarbonyl)-3-amino-1-phenylheptane 
• 129757-55-7 (S)-N-acetyl-3-amino-5-phenyl-2,2-dimethylpentane 

Relevant academic research and scientific papers

Organocerium additions to proline-derived hydrazones: Synthesis of enantiomerically enriched amines

The addition of organocerium reagents (from both organolithium and organomagnesium precursors) to chiral aldehyde hydrazones prepared from 1-aminoproline derivatives has been studied. The additions proceed in good yield and high diastereoselectivity and with good nucleophile (Me, n-Bu, i-Pr, t-Bu, Ph, etc.) and substrate scope (alkyl, alkenyl and aryl). The resulting hydrazines can be converted to amines by N-N bond cleavage through hydrogenolysis (Raney nickel) or by acylation and cleavage with Li/NH 3. The influence of the side chain on the diastereoselectivity was investigated through variation of the substituents to include more coordinating atoms (oxygen and nitrogen) as well as the removal of coordinating atoms. The SAMEMP auxiliary bearing a 2-methoxyethoxymethyl group gave the highest diastereoselectivities. Remarkably, auxiliaries bearing simple methyl and isobutyl substituents gave high selectivities as well. Hypotheses for the origin of the selectivity are presented.

Studies on the bisoxazoline- and (-)-sparteine-mediated enantioselective addition of organolithium reagents to imines

The enantioselective addition of organolithium reagents to N-anisylaldimines promoted by chiral bisoxazolines and (-)-sparteine as external ligands is described. This reaction proceeds readily with a wide range of aldimine substrates (aliphatic, aromatic, olefinic) and organolithium nucleophiles (Me, n-Bu, Ph, vinyl) in excellent yields (81-99%) and with high enantioselectivities (up to 97:3.0 er). The external ligands can be used in substoichiometric amounts albeit with slightly attenuated enantioselectivities. A systematic evaluation of the structural features of the bisoxazolines revealed a primary contribution from the substituent at C(4) and a secondary influence from the bridging substituents. A computational analysis (PM3) provided a clear rationalization for the origin of enantioselectivity.