A simple formal stereoselective synthesis of Herbarumin III

Abstract

A formal stereoselective synthesis of Herbarumin III has been accomplished starting from butanal involving Maruoka asymmetric allylation, diastereoselective iodine-induced electrophilic cyclization and conversion of iodocarbonate into syn-epoxy alcohol as the key steps.Nonenolide Phytotoxic effect Syn-epoxy alcohol Maruoka allylation Trimethylsulfonium iodide Diastereoselective iodine-induced electrophilic cyclization

Synthesis of a New Odourant, 2-Mercapto-4-Heptanol

“…However, it was a little puzzling that the 13 C NMR spectral data (Table 1) of the product we obtained did not match exactly those of the literature reference data for (1R,4R)-1,2epoxy-4-heptanol, 12 although the 1 H NMR spectral data of one diastereoisomer of our product were very close to those in the reference. The authenticity of the product we obtained was confirmed by a high resolution mass analysis.…”

“…The key intermediate, 1-hepten-4-ol, which was prepared in 87% yield by the Grignard reaction of n-butanal with allylmagnesium chloride, was epoxidised by m-chloroperoxybenzoic acid to 1,2-epoxy-4-heptanol in 92% yield as a mixture of two diastereoisomers with a ratio of 56/44 (determined by GC and confirmed by 1 H NMR spectral data). However, it was a little puzzling that the 13 C NMR spectral data (Table 1) of the product we obtained did not match exactly those of the literature reference data for (1R,4R)-1,2epoxy-4-heptanol, 12 although the 1 H NMR spectral data of one diastereoisomer of our product were very close to those in the reference. The authenticity of the product we obtained was confirmed by a high resolution mass analysis.…”