25756-06-3

Upstream product

• 55134-78-6 3-methyl-5-phenyl-2-trimethylsilanyloxy-isoxazolidine 
• 7064-06-4 3-methyl-5-phenyl-4,5-dihydroisoxazole 
• 18312-45-3 propan-2-one O-acetyl oxime 
• 100-52-7 benzaldehyde 
• 23652-90-6 3-amino-1-phenylbut-2-en-1-one 
• 56894-87-2 4-acetoxy-4-phenyl-butan-2-one 
• 5381-93-1 1-hydroxy-1-phenyl-3-butanone 
• 753386-78-6 3-Amino-1-phenyl-butan-1-one 
• 95633-12-8 3-benzyloxyimino-1-phenyl-1-butanol 
• 89762-98-1 anti-3-benzyloxyimino-1-phenyl-1-butanol 

Downstream Products

• 73406-38-9 cis-4-methyl-6-phenyltetrahydro-2H-1,3-oxazin-2-one 
• 73406-39-0 c-4-Methyl-c-6-phenyl-r-2-(4-nitrophenyl)tetrahydro-1,3-oxazin 
• 42142-54-1 erythro-3-Methylamino-1-phenyl-butanol 
• 184303-07-9 [(1-Methyl-3-oxo-3-phenyl-propyl)-(toluene-4-sulfonyl)-amino]-acetic acid benzyl ester 

Relevant academic research and scientific papers

Selective access to all four diastereomers of a 1,3-amino alcohol by combination of a keto reductase- and an amine transaminase-catalysed reaction

The biocatalytic synthesis of chiral amines has become a valuable addition to the chemists' toolbox. However, the efficient asymmetric synthesis of functionalised amines bearing more than one stereocentre, such as 1,3-amino alcohols, remains challenging. By employing a keto reductase (KRED) and two enantiocomplementary amine transaminases (ATA), we developed a biocatalytic route towards all four diastereomers of 4-amino-1-phenylpentane-2-ol as a representative molecule bearing the 1,3-amino alcohol functionality. Starting from a racemic hydroxy ketone, a kinetic resolution using an (S)-selective KRED provided optically active hydroxy ketone (86% ee) and the corresponding diketone. Further transamination of the hydroxy ketone was performed by either an (R)- or an (S)-selective ATA, yielding the (2R,4R)- and (2R,4S)-1,3-amino alcohol diastereomers. The remaining two diastereomers were accessible in two subsequent asymmetric steps: the diketone was reduced regio- and enantioselectively by the same KRED, which yielded the (S)-configured hydroxy ketone. Eventually, the subsequent transamination of the crude product with (R)- and (S)-selective ATAs yielded the remaining (2S,4R)- and (2S,4S)-diastereomers, respectively.

Stereoselective reduction of enaminones to syn γ-aminoalcohols

One-pot reduction of enaminones to syn γ-aminoalcohols can be efficiently performed by lithium borohydride in the presence of cerium chloride as Lewis acid. Selectivities are very good with respect to classical reduction method of these products.

Generation of chromioenamines by reduction of O-acetyloximes with chromium(II) and their application

Chromioenamines can be generated by treatment of O-acetyloximes with chromium(II) via two steps of one-electron reduction and successive isomerization, and the species react with aldehydes to give γ-amino alcohols after reduction with LiA1H4.

Stereoselective Preparation of Acyclic syn-β-Amino Alcohols from β-Hydroxy Ketones via the Corresponding O-Benzyl Oximes

Reduction of β-hydroxy ketone O-benzyl oximes with lithium aluminum hydride in the presence of sodium or potassium methoxide afforded the corresponding syn-β-amino alcohols in highly stereoselective manner.A lythraceae alkaloid, lasubine II, was synthesiz

STEREOSELECTIVE PREPARATION OF ACYCLIC syn-1,3-AMINO ALCOHOLS FROM β-HYDROXY KETONES

syn-1,3-Amino alcohols are prepared in good yields by the stereoselective reduction of β-hydroxy-ketone-O-benzyloximes derived from acyclic β-hydroxy ketones with lithium aluminium hydride.

A FACILE METHOD FOR THE STEREOSELECTIVE PREPARATION OF ACYCLIC syn-1,3-AMINO ALCOHOLS FROM β-HYDROXY KETONES

Treatment of acyclic β-hydroxy ketones with O-benzyl-hydroxylamine hydrochloride gave a mixture of stereoisomers of the corresponding O-benzyloximes.The mixture of the both isomers was reduced with lithium aluminum hydride in the presence of sodium or pot

Synthesis via Isoxazolines, 5. - 1,3-Asymmetric Induction in the reduction of 3,5-Disubstituted 2-Isoxazolines; Diastereoselective Synthesis and Configurational Assignment of γ-Amino Alcohols

The cycloaddition of nitrile oxides to alkenes, followed by reduction of the ensuing 2-isoxazolines 3, yields γ-amino alcohols 4 in a regioselective manner.The stereoselectivity of the reduction step is examined; it is highest with LiAlH4 as the reducing agent. 1,3-Asymmetric induction by isoxazoline ring substituents leads to β-4:α-4 ratios of ca. 85:15 for 5-methyl and ca. 95:5 for 5-phenyl. (CH3)2S-BH3, less selectively, furnishes 60:40, Na-Hg and Na/ethanol reduction give rise to 40:60 diastereomer mixtures.From these, two amino alcohols of the α-series are isolated. 3a is reduced by NaBH3CN to give cis/trans-isoxazolines 11. - The relative configurations of β- and α-4 and, consequently, the steric course of these reductions, are established by 1H- and 13C-NMR studies of 4 as well as of cyclic derivatives (azetidine 7, tetrahydro-1,3-oxazine 10).In addition, conformations of the free amino alcohols 4 are suggested on the basis of 13C-NMR data.