159701-46-9

Upstream product

• 135214-52-7 (S)-(2-benzyloxiran-2-yl)methanol 
• 90926-14-0 rac-2-methyl-3-phenyl-1,2-propanediol 
• 36099-42-0 (+/-)-2-methyl-3-phenyl-1,2-epoxypropane 
• 30457-89-7 2-benzylallyl alcohol 
• 20593-63-9 2-Benzylacrylic acid ethyl ester 
• 135107-04-9 (±)-(2-benzyloxiran-2-yl)methanol 
• 6921-34-2 benzylmagnesium chloride 
• 165881-60-7 (R)-2-benzyl-2-methyloxirane 

Relevant academic research and scientific papers

Biocatalytic resolution of 2-methyl-2-(aryl)alkyloxiranes using novel bacterial epoxide hydrolases

Biocatalytic resolution of alkyl- and (arylalkyl)-oxiranes was accomplished by employing the epoxide hydrolase activity of lyophilized whole cells of seven bacterial strains belonging to the genera Rhodococcus, Mycobacterium and Nocardia. Whereas no suita

Deracemization of (±)-2,2-disubstituted epoxides via enantioconvergent chemoenzymatic hydrolysis using nocardia EH1 epoxide hydrolase and sulfuric acid

2-Substituted (S)-1,2-diols were prepared in a one-pot procedure with >90% ee and >90% isolated yield via deracemization of (±)-2,2-disubstituted oxiranes through sequential (i) biocatalytic asymmetric hydrolysis using Nocardia EH1 epoxide hydrolase and (

Enantioselective pseudomonas fluorescens (P. Cepacia) Lipase-Catalyzed irreversible transesterification of 2-Methyl-1,2-Diols in an organic solvent

The Pseudomonas fluorescens (P. cepacia) lipase-catalyzed irreversible transesterification of 2-phenyl-1,2-propanediol in is not enantioselective, whereas the diols 1b and 1c are enzymatically resolved with the same procedure to (S)-1b and 1c (>98 and 92% e.e.) and the (R)-acetates 2b and 2c (92% e.e.).

Phase-transfer catalyzed enantioselective α-alkylation of α-acyloxymalonates: Construction of chiral α-hydroxy quaternary stereogenic centers

The enantioselective synthesis of α-acyloxy-α-alkylmalonates was developed as an efficient method for producing chiral α-tertiary alcohols, which are potentially valuable intermediates in the synthesis of natural products and pharmaceuticals. The efficient enantioselective α-alkylation of diphenylmethyl tert-butyl α-acyloxymalonates was accomplished via phase-transfer catalysis in the presence of (S,S)-3,4,5-trifluorophenyl-NAS bromide to afford the corresponding α-acyloxy-α-alkylmalonates at high chemical (up to 99%) and optical (up to 93% ee) yields, which could be readily converted to versatile chiral intermediates with a chiral α-tertiary alcohol group.

Diastereoselective addition of grignard reagents to chiral α-ketoimides derived from Oppolzer's sultam

Additions of various Grignard reagents to N-pyruvoyl- (3) and N-phenylglyoxyloyl-(2R)-bornane-10,2-sultam (4) under thermal and Lewis-acid catalytic conditions are studied. High diastereoselectivity was observed in these reactions, and in the case of vinylmagnesium bromide additions to α-ketoimide 4 a change of direction of asymmetric induction was found.

Chemoenzymatic deracemization of (±)-2,2-disubstituted oxiranes

The preparation of vicinal diols in up to 98% e.e. and 98% yield from the corresponding (±)-2,2-disubstituted epoxides was achieved via an enantioconvergent two-step hydrolysis: Thus, enantioselective enzymatic hydrolysis of the (S)-epoxide proceeded with retention of configuration furnishing the corresponding (S)-diol. In a subsequent step, the remaining (R)-oxirane was hydrolyzed during workup under acid catalysis with complete inversion of configuration yielding the (5)-diol. A detailed study of the latter reaction revealed that the experimental conditions have to be carefully chosen with respect to (i) nature of the acid, (ii) the solvent, and (iii) its water content to avoid racemization.

An efficient] large-scale synthesis of (R)-(-)-mevalonolactone using simple biological and chemical catalysts

Natural (R)-(-)-mevalonolactone (2) was synthesized in eight steps in 55% total yield and >99% ee employing an enantioconvergent chemoenzymatic route. In the key step, 2-benzyl-2-methyloxirane (±)-3 was deracemized on a large scale (10 g) using lyophilized cells of Nocardia EH1 and sulfuric acid. The product diol (S)-4 was isolated in 94% chemical yield and 94% optical purity.

N-Boc 2-acyloxazolidines: Useful precursors to enantiopure 1,2-diols via highly diastereoselective nucleophilic additions

N-Boc 2-Acyloxazolidines were synthesized from norephedrine and phenylglycinol. This preparation involves: (i) a transformation or the above β-amino alcohols into N-Boc 2-ethoxycarbonyloxazolidines, (ii) the formation of the corresponding Weinreb amides and, (iii) a reaction between these amides and organometallic reagents. Such diastereomerically pure heterocycles react cleanly with various nucleophilic reagents (Grignard reagents, sodium borohydride and allylsilane) to afford the corresponding alcohols. Treatment of these hydroxyoxazolidines with trifluoro acetic acid, followed by hydrolysis and reduction of the intermediate α-hydroxy aldehydes afforded 1,2-diols. The overall transformation exhibited in most cases a complete diastereoselectivity which can be explained by a chelated model for the nucleophilic addition.

Enantioselective Synthesis of 2-Methyl-2-hydroxy-γ-butyrolactone and Its Application in the Asymmetric Synthesis of Frontalin and Mevalonolactone

The asymmetric hydroxylation of the enolates of fully substituted acyclic ester 8 and lactone 10 with (camphorylsulfonyl)oxaziridines 1a - c was studied.The stereoselectivities of the tertiary α-hydroxy carbonyl products were highly dependent on the enolate structure, the oxidizing reagents, and the reaction conditions.While high diastereoselectivity (up to 94percent) was obtained for enolates of fully substituted menthol ester 8 with substoichiometric amounts of oxaziridine 1a, the yields were unsatisfactory.On the other hand, the enantioselective α-hydroxylation of the sodium enolate of 2-methyl-γ-butyrolactone (10) with oxaziridine (1c) afforded α-hydroxy lactone 11a in 70percent yield and 84percent ee.The enantiomeric excess was improved to >93percent ee by crystallization of the corresponding benzoyl ester 11c.The utility of both enantiomers of 11c were demonstrated in the formal asymmetric syntheses of the pheromone, (1S,5R)-(-)-frontalin (13) and in the asymmetric synthesis of (R)-(-)-mevalonolactone (20).