132331-33-0Relevant academic research and scientific papers
Exopericyclic stereocontrol in Johnson-Claisen rearrangements of allylic sulfides
Craig, Donald,Harvey, John W.,O'Brien, Alexander G.,White, Andrew J. P.
supporting information; experimental part, p. 6932 - 6934 (2010/11/04)
A study of the effects of exopericyclic stereocentres on the stereoselectivity of Johnson-Claisen rearrangements of thioether-containing allylic alcohols shows that selectivity is highly dependent upon allylic substitution patterns.
ORGANOCATALYSTS AND METHODS OF USE IN CHEMICAL SYNTHESIS
-
Page/Page column 54-56; 106-108, (2010/02/15)
The present invention pertains generally to compositions comprising organocatalysts that facilitate stereo-selective reactions and the method of their synthesis and use. Particularly, the invention relates to metal-free organocatalysts for facilitation of stereo--selective reactions, and the method of their synthesis and use. These compounds have the structure of the Formulas (I) and (II). Where X is independently selected from CH2, N-Ra, O, S or C=O; Y is CH2, N-Ra, O, S or C=O, with the proviso that at least one of X or Y is CH2, and preferably both of X and Y are CH2; Ra is H, an optionally substituted C1-C12 alkyl, preferably an optionally substituted C1-C6alkyl including a C3-C6 cyclic alkyl group, or an optionally substituted aryl group, preferably an optionally substituted phenyl group; Rb is H, an optionally substituted C1-C12 alkyl, preferably an optionally substituted C1-C6 acyclic or a a C3-C6 cyclic alkyl group, CHO, N(Me)O, CO(S)Ra or the group of Formula (III). Where Rc and Rd are each independently H, F, C1, an optionally substituted C1-C20 alkyl, preferably an optionally substituted C1-C12 alkyl, more preferably a C1-C6 alkyl, and an optionally substituted aryl group, or together Rc and Rd form an optionally substituted carbocyclic or optionally substituted heterocyclic ring; R1 is OH, OR, NR'R", NHC(=O)R, NHSO2R; R2 is H, F, C1, an optionally substituted C1-C20 alkyl, preferably an optionally substituted C1-C6 alkyl, an optionally substituted aryl group or a =O group (which establishes a carbonyl group with the carbon to which =O is attached; R3 is H, OH, F, C1, Br, I, Cl, an optionally substituted C1-C20 alkyl, alkenyl or alkynyl ("hydrocarbyl") group, preferably an optionally substituted C1-C6 alkyl, or an optionally substituted aryl, such that the carbon to which R3 is attached has an R or S configuration; R is H, an optionally substituted C1-C20 alkyl, preferably an optionally substituted C1-C6 alkyl, or an optionally substituted aryl group, R' and R" are each independently H, an optionally substituted C1-C20 alkyl group, preferably an optionally substituted C1-C6 alkyl, or an optionally substituted aryl group; or together R' and R" form an optionally substituted heterocyclic, preferably a 4 to 7 membered optionally substituted heterocyclic group or an optionally substituted heteroaryl ring with the nitrogen to which R' and R" are attached; and wherein said compound is free from a metal catalyst.
Do the electronic effects of sulfur indeed control the π-selectivity of γ-sulfenyl enones? An investigation
Yadav, Veejendra K.,Babu, K. Ganesh,Parvez, Masood
, p. 3866 - 3874 (2007/10/03)
The electronic effects of sulfur in γ-sulfenyl enones are not transmitted to the carbonyl carbon through the π bond as reported previously. The diastereoselectivity is rather controlled by a combination of several other factors. The steric effects arising
Direct, organocatalytic α-sulfenylation of aldehydes and ketones
Wang, Wei,Li, Hao,Wang, Jian,Liao, Lixin
, p. 8229 - 8231 (2007/10/03)
A method for direct sulfenylation of aldehydes and ketones, catalyzed by a novel pyrrolidine trifluoromethanesulfonamide organocatalyst, has been developed. This process serves as an efficient and mild approach to the preparation of α-phenylthio-ketones and -aldehydes.
Kinetic resolution in asymmetric anti aldol reactions of branched and straight chain racemic 2-phenylsulfanyl aldehydes: Asymmetric synthesis of cyclic ethers and lactones by phenylsulfanyl migration
Chibale, Kelly,Warren, Stuart
, p. 1935 - 1940 (2007/10/03)
The kinetic resolution of branched and straight chain 2-phenylsulfanyl aldehydes by the Lewis acid-catalysed asymmetric anti aldol reaction followed by reduction to single enantiomers of 1,3-diols and/or acid-catalysed cyclisation with PhS migration provides a route to enantiomerically pure cyclic ethers and lactones with full stereochemical control.
The synthesis of optically active 2-phenylthio aldehydes
Chibale, Kelly,Warren, Stuart
, p. 3991 - 3994 (2007/10/02)
Optically active linear and branched chain 2-phenylthio aldehydes can be made in high optical purity (up to > 98% e.e.) by sulfenylation of a phenylalanine-derivative oxazolidinone imide, reduction and re-oxidation with the Dess-Martin reagent even though the products enolise easily.
Synthesis of Enantiomerically Enriched α-Sulfenylated Ketones and Aldehydes
Youn, Joo-Hack,Herrmann, Rudolf,Ugi, Ivar
, p. 159 - 161 (2007/10/02)
α-Sulfenylated carbonyl compounds are prepared by the reaction of imines of aldehydes and ketones containing α-hydrogens with disulfides via the metalloenamines.With (R)-α-phenylethylamine as chiral auxiliary, enantiomeric excess of 13-51percent are obser
