80928-05-8

Upstream product

• 1234714-03-4 (S)-N-tert-butoxy-N-1'-(1''-naphthyl)ethyl (R)-2-benzyloxypent-4-enamide 
• 167563-04-4 ((E)-(R)-1-Ethyl-hept-2-enyloxymethyl)-benzene 
• 80952-62-1 (2S,3S,4R)-4-Benzyloxy-hexane-2,3-diol 
• 80952-66-5 (2S,3R,4R)-4-Benzyloxy-hexane-2,3-diol 
• 100-44-7 benzyl chloride 
• 80952-65-4 (2R,3S)-2-((R)-1-Benzyloxy-propyl)-3-methyl-1,4-dioxa-spiro[4.5]decane 
• 80952-61-0 (2S,3S)-2-((R)-1-Benzyloxy-propyl)-3-methyl-1,4-dioxa-spiro[4.5]decane 
• 100-39-0 benzyl bromide 

Downstream Products

• 84994-62-7 (R)-2-(benzyloxy)butan-1-ol 
• 1043481-68-0 (2R,2S)-(-)-(E)-N-(2-benzyloxybutylidene)-N-(2-methoxymethylpyrrolidin-1-yl)amine 
• 80928-09-2 (6S,7R)-7-Benzyloxy-6-hydroxy-nonan-2-one 
• 80928-08-1 (4S,5R)-5-Benzyloxy-1-(2-methyl-[1,3]dioxolan-2-yl)-heptan-4-ol 

Relevant academic research and scientific papers

Alkylation and aldol reactions of acyl derivatives of N-1-(1′-naphthyl)ethyl-O-tert-butylhydroxylamine: asymmetric synthesis of α-alkoxy-, α-substituted-β-alkoxy- and α,β-dialkoxyaldehydes

Treatment of a range of O-protected glycolate derivatives of the chiral auxiliary N-1-(1′-naphthyl)ethyl-O-tert-butylhydroxylamine with KHMDS in the presence of 18-crown-6 followed by addition of an alkyl halide generates α-substituted derivatives with very high levels of diastereoselectivity. Alternatively, reaction of the potassium enolate of a propanoate or O-protected glycolate derivative of N-1-(1′-naphthyl)ethyl-O-tert-butylhydroxylamine with a range of aldehydes gives syn-aldol products with high levels of diastereoselectivity. These adducts may be reductively cleaved with LiAlH4 to give enantiopure α-alkoxy-, α-substituted-β-alkoxy- and α,β-dialkoxyaldehydes in good yield.

Diastereo- and enantioselective synthesis of 1,2-amino alcohols and protected α-hydroxy aldehydes from glycol aldehyde hydrazones

Starting from chiral glycol aldehyde hydrazones (S)-2, we prepared differently protected α-hydroxy aldehydes (R)- or (S)-4 as well as N-acetyl-protected 1,2-amino alcohols (R)-11 in high enantiomeric excesses via azaenolate α-alkylation or nucleophilic 1,2-addition to the CN double bond. The successive introduction of two vicinal stereogenic centres opens a new, flexible syn-diastereo- and enantioselective route to functionalised, N-acetyl-protected, vicinal amino alcohols (R,R)-13, which was demonstrated in the case of the γ-amino-β-hydroxycarboxylic acid statin (R,R)-15 and its analogues B. VCH Verlagsgesellschaft mbH, 1996.

Steric and Electronic Effects in Conformational Preferences of C1-Oxygenated Chiral Alkenes

A variable temperature NMR study shows that the benzyl protective group on the hydroxy function of a chiral allylic alcohol enhances the CH eclipsed from (I).On the other hand, various silyl ethers enhance the preference for the CO eclipsed conformer.However, when both the allylic R group and the hydroxy protective group are bulky (R = tert-butyl, P = TIPS), the staggered conformation of the chiral alkene becomes preferred.An acetate group does not have an apparent effect on the conformational preference of the protected allylic alcohol.These facts are explained in terms of steric and electronic interactions.

ON THE STERIC COURSE OF ADDITION OF GRIGNARD REAGENTS ONTO α,β-DIALKOXY ERYTHRO AND THREO CHIRAL ALDEHYDES. SYNTHESIS OF (+) AND (-)-EXO AND ENDO-BREVICOMIN

Addition of BrMgCH2CH3 onto the erythro and threo aldehydes (1) and (2) to form (3)+(6) and (9)+(10) proceeds with 6:4 and 8:2 threo-erythro selectivity, respectively.From (3) and (6), (2S) and (2R)-2-benzyloxy butyraldehyde (13) and (14) have been prepared.Addition of ClMgCH2CH2CH2(COCH2CH2O)CH3 onto (13) and (14) proceeds with 6:4, threo-erythro selectivity, to give after preparative gas chromatographic separation, the enantiomeric forms of exo- and endo-brevicomin (19), (21) and (20), (22).