An unprecedented tandem 1,3-dipolar cycloaddition-cheletropic elimination: a facial approach to novel push-pull olefins.

Chemistry Department, Beijing Normal University, Beijing, 100875, China.
Organic & Biomolecular Chemistry (Impact Factor: 3.57). 05/2007; 5(8):1282-6. DOI: 10.1039/b701326d
Source: PubMed

ABSTRACT The interaction of 2-(phenylthiocarbamoyl) imidazolium inner salts with dimethyl acetylenedicarboxylate produced dimethyl 2-(imidazolin-2-ylidene)-3-thioxobutanedioates in moderate to good yields. The process involved a tandem reaction comprising a 1,3-dipolar cycloaddition and an unprecedented cheletropic elimination of the phenyl isonitrile from a 2-phenyliminodihydrothiophene moiety. NMR and X-ray diffraction studies confirmed that the 2-(imidazolin-2-ylidene)-3-thioxobutanedioates are novel push-pull olefins and have potential applications in nonlinear optical materials.

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