89393-53-3

Upstream product

• 59983-39-0 (S)-1-amino-2-(methoxymethyl)pyrrolidine 
• 98-86-2 acetophenone 

Downstream Products

• 109012-78-4 dimethyl (2'S,2R)-(+)-4-<2-(methoxymethyl)pyrrolidinoimino>-2,4-diphenyl-1,1-butanedicarboxylate 
• 109033-99-0 dimethyl (2'S,2R)-(+)-2-(-4-benzyloxy-3-methoxyphenyl)-4-<2-(methoxymethyl)pyrrolidinoimino>-4-phenyl-1,1-butanedicarboxylate 
• 1246844-77-8 2-methoxymethyl-1-[N-methoxycarbonyl-N-(1-phenylethyl)amino]pyrrolidine 
• 107300-20-9 (2S,2''R)-2-methoxymethyl-1-[N-methoxycarbonyl-N-(1-phenylethyl)amino]pyrrolidine 
• 89393-73-7 methyl (3R)-3-methyl-5-oxo-5-phenylpentanoate 
• 109012-80-8 (2'S,2R)-(+)-4-<2-(methoxymethyl)pyrrolidinoimino>-2-(4-methoxyphenyl)-4-phenyl-1,1-dicarbonitrile 

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.

Asymmetric Michael Additions via SAMP-/RAMP-Hydrazones Enantioselective 1,4-Addition of Methyl Ketones to Knoevenagel Acceptors

Asymmetric Michael addition of lithiated methyl ketone SAMP-hydrazones (S)-2 to 2-benzylidenemalonates and -dinitriles 3 followed by oxidative cleavage of the 1,4-adducts (SR)-4 by ozonolysis affords 2-substituted 4-oxo diesters and -dinitriles (R)-5 in good overall yields of 50-82percent and high enantiomeric excesses (ee >/= 95percent).

ASYMMETRIC SYNTHESIS OF β-SUBSTITUTED δ-KETOESTERS VIA MICHAEL-ADDITIONS OF SAMP/RAMP-HYDRAZONES TO α,β-UNSATURATED ESTERS, VIRTUALLY COMPLETE 1.6-ASYMMETRIC INDUCTION

A simple and efficient 3-step asymmetric synthesis of β-substituted δ-ketoesters 3 in 45-62percent overall chemical yield and >=96-ca.100percent ee is described.The key step is an asymmetric Michael-addition of lithiated methylketone-SAMP- or RAMP-hydrazones to α,β-unsaturated esters 2 with virtually complete 1.6-asymmetric induction.