A synthesis of (1E,3E)-TMS dienes from keto-xanthates via Chugaev-type elimination
Kelvin Kau Kiat Goh1, Sunggak Kim, Samir Z Zard
1Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University , Singapore 637371, Singapore.
Abstract:
An efficient route leading to exclusively (1E,3E)-TMS dienes is described. Radical xanthate addition of keto-xanthates to vinyltrimethylsilane followed by one-pot Chugaev elimination/cyclization and in situ oxidation with m-CPBA afforded the corresponding TMS 2-sulfolenes. Isomerization to 3-sulfolenes by the action of DBU with the extrusion of sulfur dioxide in refluxing toluene gave the titled (1E,3E)-TMS dienes.
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