Universal remedy: The α‐hydroxylation of β‐keto esters and a range of other suitably substituted carbonyl compounds can be effected in the presence of IBX (2‐iodoxybenzoic acid). This novel reactivity underscores the importance of IBX as a universally applicable oxidizing agent.
Asymmetric Synthesis of Trisubstituted Tetrahydrothiophenes Bearing a Quaternary Stereocenter via Double Michael Reaction Involving Dynamic Kinetic Resolution
The stereoselective synthesis of highly functionalized tetrahydrothiophenes bearing threecontiguousstereocenters, one of them quaternary, can be achieved by reacting trans-α-cyano-α,β-unsaturated ketones and trans-tert-butyl 4-mercapto-2-butenoate in the presence of a readily available amine thiourea. The products are obtained in high yield, good diastereoselectivity, and excellent enantioselectivity
IBX-Mediated Dehydrogenation of Substituted β-Oxonitriles
作者:Philipp Klahn、Stefan F. Kirsch
DOI:10.1002/ejoc.201402007
日期:2014.5
convenient method for the mild dehydrogenation of β-oxonitriles is presented. When treated with o-iodoxybenzoic acid (IBX), a range of these compounds were transformed into their unsaturated counterparts. Furthermore, we show that the products of the dehydrogenation can react in situ, undergoing rapid hetero-Diels–Alder reactions with enol ethers to give multiply substituted dihydropyrans. We also describe
An effective one-pot sequential Michael addition/deprotection/cyclization/tautomerization approach to N-unprotected fully substituted trans-2-pyrrolines has been developed.