51559-18-3

Upstream product

• 69489-16-3 (S)-(+)-2-hydroxy-2-phenyl-3-methylbutyraldehyde 
• 590-86-3 isovaleraldehyde 
• 611-70-1 phenyl isopropyl ketone 
• 599192-45-7 (1S,2R,5R,7S,9R)-5-benzoyl-10,10-dimethyl-4-oxa-6-thiatricyclo[7.1.1.0^2,7]undecane 
• 682352-10-9 (1S,2R,3S,5R,2'S)-6,6-dimethyl-3-(2'-ethoxy-1'-phenyl-1'-oxo-2'-ethylsulfanyl)-2-(O-t-butyl-dimethylsilyl-hydroxymethyl)-bicyclo[3.1.1]heptane 
• 682352-08-5 (1S,2R,3S,5R,2'S)-6,6-dimethyl-3-(2'-ethoxy-1'-phenyl-1'-oxo-2'-ethylsulfanyl)-2-hydroxymethyl-bicyclo[3.1.1]heptane 
• 6175-45-7 2,2-diethoxyacetophenone 
• 677031-97-9 (Z,4R)-4-isopropyl-3-(3'-methyl-2'-phenylbut-1'-enyl)oxazolidin-2-one 
• 101-41-7 benzeneacetic acid methyl ester 
• 90499-41-5 2-phenyl-3-methylbutanol 
• 72615-27-1 2-phenyl-3-methylbutyric acid methyl ester 
• 2439-44-3 3-methyl-2-phenylbutanal 
• 677032-06-3 (4R,3'S,4'S)-4-isopropyl-3-[4'-phenyl-4'-(1''-phenylethyl)[1',2']dioxetan-3'-yl]oxazolidin-2-one 
• 682352-14-3 (1S,2R)-1-[(1S,2R,3S,5R)-2-(tert-Butyl-dimethyl-silanyloxymethyl)-6,6-dimethyl-bicyclo[3.1.1]hept-3-ylsulfanyl]-1-ethoxy-3-methyl-2-phenyl-butan-2-ol 

Downstream Products

• 69489-16-3 (S)-(+)-2-hydroxy-2-phenyl-3-methylbutyraldehyde 
• 281223-05-0 endo-(4S)-2-oxo-4-isopropyl-4-phenyl-1,3,2-dioxathiolane 
• 281223-06-1 exo-(4S)-2-oxo-4-isopropyl-4-phenyl-1,3,2-dioxathiolane 

Relevant academic research and scientific papers

Resolution of diols via catalytic asymmetric acetalization

A highly enantioselective kinetic resolution of diols via asymmetric acetalization has been achieved using a chiral confined imidodiphosphoric acid catalyst. The reaction is highly efficient for the resolution of tertiary alcohols, giving selectivity factors of up to >300. Remarkably, even in cases where the selectivity factors are only moderate, highly enantioenriched diols are obtained via a stereodivergent resolution to diastereomeric acetals.

Electronic polarizability-based stereochemical model for Sharpless AD reactions

Softness really is the hard force! Reported here was the critical yet long-overlooked role of electronic polarizability (i.e., softness) effect in controlling absolute stereochemical courses of general asymmetric induction events. Thus, a sensitive dependence of the sense of chiral induction on an alkene substrate's substituent electronic polarizability character was uncovered from a range of structurally highly comparable Sharpless asymmetric dihydroxylation (AD) systems, from which a new polarizability-based stereochemical model of predictive power was suggested.

Enecarbamates as Selective Substrates in Oxidations: Chiral-Auxiliary-Controlled Mode Selectivity and Diastereoselectivity in the [2+2] Cycloaddition and Ene Reaction of Singlet Oxygen and in the Epoxidation by DMD and mCPBA

The stereochemical course of the oxidation of chiral oxazolidinone-substituted enecarbamates has been studied for singlet oxygen (1O2), dimethyldioxirane (DMD), and m-chloroperbenzoic acid (mCPBA) by examining of the special structural and stereoelectronic features of the enecarbamates. Valuable mechanistic insight into these selective oxidations is gained. Whereas the R1 substituent on the chiral auxiliary is responsible for the steric shielding of the double bond and determines the sense of the π-facial diastereoselectivity, structural characteristic such as the Z/E configuration and the nature of the R 2 group on the double bond are responsible for the extent of the diastereoselectivity. Stereoelectronic steering by the vinylic nitrogen functionality controls the mode selectivity (ene reaction vs [2+2] cycloaddition) in the case of 1O2.

New S,O-acetals from (1R)-(-)-myrtenal as chiral auxiliaries in nucleophilic additions

Treatment of hydroxythiol 4 with α,α-diethoxyacetophenone at room temperature yielded a mixture of epimeric S,O-acetals 6 and 7 (1:4, 92% yield), which were efficiently separated by flash chromatography. The OTBS derivatives 8 and 9 were treated with several Grignard reagents to afford carbinols 10 and 13 respectively (85-99% yield, >95% dr). After successive hydrolysis and reduction of 10 and 13 it is possible to obtain either enantiomer of diols 16 in high optical purity (>95% er).

Enantioselective synthesis of 1-alkyl-substituted 1-phenyl-1,2-ethanediols using a myrtenal-derived chiral auxiliary

The enantioselective synthesis of several 1-phenyl-1,2-ethanodiol derivatives using 2-benzoyl-1,3-oxathiane 1 as a chiral auxiliary is described. Nucleophilic additions of Grignard reagents, methyl lithium and LS-Selectride on benzoyloxathiane 1 proceeded in >95% diastereomeric ratio (dr) affording the corresponding tertiary carbinols, which were successively hydrolyzed and reduced to give the title derivatives in >95% enantiomeric excess (ee).

Camphor-derived 2-stannyl-N-Boc-1,3-oxazolidine: A new chiral formylanion equivalent for the asymmetric synthesis of 1,2-diols

Optically pure 2-tributylstannyl-N-Boc-1,3-oxazolidine 6, prepared from the camphor-derived aminoalcohol 5, was converted to diastereomerically pure 2-acyl derivatives 8 in three steps. Reaction of these ketones with Grignard reaagents at -78°C proceeded with high stereoselectivity affording tertiary carbinols which gave 1,2-diols with >96% ee after hydrolysis and reduction of the intermediate α-hydroxy aldehydes. A new deblocking procedure of the t-Boc group is also described.