65651-53-8

Upstream product

• 72748-99-3 (R)-1-Amino-2-(methoxymethyl)pyrrolidine 
• 78-93-3 butanone 
• 59983-39-0 (S)-1-amino-2-(methoxymethyl)pyrrolidine 

Downstream Products

• 175430-84-9 (+)-(2S,2'S)-1-<2'-(t-Butyldimethylsilyl)-1'-phenylpent-3'-ylideneamino>-2-methoxymethylpyrrolidine 
• 175430-93-0 (2S,3'S)-1-<3'-(Dimethylphenylsilyl)hex-4'-ylideneamino>-2-methoxymethylpyrrolidine 
• 175430-92-9 (2S,2'S)-1-<2'-(Dimethylphenylsilyl)pent-3'-ylideneamino>-2-methoxymethylpyrrolidine 
• 175430-76-9 (2S)-1-<1'-(Dimethylphenylsilyl)but-2'-ylideneamino>-2-methoxymethylpyrrolidine 
• 109012-79-5 dimethyl (2'S,2R)-2-(-4-benzyloxy-3-methoxyphenyl)-4-<2-(methoxymethyl)pyrrolidinoimino>-1,1-hexanedicarboxylate 
• 89393-63-5 (R)-5-[(E)-(S)-2-Methoxymethyl-pyrrolidin-1-ylimino]-3-phenyl-heptanoic acid methyl ester 

Relevant academic research and scientific papers

First highly efficient asymmetric synthesis of the Hyrtios erectus diketotriterpenoid

The first highly efficient asymmetric synthesis of the diketotriterpenoid 1, isolated from the Indonesian marine sponge Hyrtios erectus, in good overall yield and employing simple starting materials such as butanone, is described. Both stereogenic centres at the C-6 and C-19 positions of the C2-symmetrical molecule were generated via α-alkylation employing the SAMP/RAMP hydrazone method with high asymmetric inductions (de, ee ≥ 96%). The absolute configuration of the natural material was determined as R,R.

Regio-, Diastereo-, and Enantioselective Synthesis of vic-Diols via α-Silyl Ketones According to the SAMP/RAMP Hydrazone Method

α-Silylated ketones 5 or 10 of high enantiomeric purity (ee>=90percent) are easily available by silylation or silylation/alkylation of ketones 1 or 6, resp., according to the SAMP/RAMP hydrazone method.Reduction of 5 or 10 with L-selectride, followed by oxidative cleavage of the C-Si bond, leads to vic-diols 11-13 with high diastereoselectivity (de>=90percent) and without racemization.The stereoselectivity of the reduction depends on the structure of the α-silyl ketones 5 or 10, the reducing reagents, and the solvents used.Key Words: Ketones, α-silyl / vic-Diols, diastereo- and enantioselective synthesis / SAMP/RAMP Hydrazones / L-Selectride reductions

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.