As eries of stable phosphonium salts have been synthesized via an ovel four-component reaction of an arene nucleophile,2 -heteroatom substituted aryl aldehyde,a nd phosphine in presence of an acid. The phosphonium salts thus obtained were utilized for the synthesis of avariety of bisheteroarenes,p roviding an efficient alternative method to the classical cross-coupling strategies.Scheme 2. Proposed retrosynthetic approach for the synthesis of bisheteroarenes.

A phosphine-mediated reaction for the construction of spirocyclopenta[c]chromene-indolinones is reported via a Rauhut-Currier (RC)-type/ acyl transfer/Wittig sequence. This methodology attributes the chemoselective phosphine addition to the alkynoate which generates the phosphorus zwitterion via RC-type reaction, and that further undergoes O-acylation to form the seven-membered betaine intermediate with acyl chloride in the presence of base. Extensive investigations reveal that the exceptional δ-acylation occurs through the CÀ O bond cleavage upon the seven-membered betaine, and the subsequent Wittig reaction preferentially result in the aforementioned spiro compounds. Furthermore, our protocol could also be applicable to different alkynoates to provide a series of spirocyclopenta[c]chromenones bearing privileged skeletons.

The title reaction, catalyzed by a cinchona‐alkaloid derivative, delivers almost diastereo‐ and enantiomerically pure γ,γ‐disubstituted butenolides with adjacent tertiary and quaternary stereocenters.

No abstract

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.