86318-60-7Relevant articles and documents
Thioketene Syntheses, VII. Substituent Effects on the Thio-Claisen Rearrangement of Alkynyl Allyl Sulfides
Schaumann, Ernst,Lindstaedt, Joerg
, p. 1728 - 1738 (2007/10/02)
Electron acceptors in the position 2 of the allyl residues in alkynyl allyl sulfides 4, 11, 15 favor the Thio-Claisen rearrangement to give thioketenes 5, 12, 16, but in position 3 impede the reaction.For the substituent on the triple bond, the sequence silyl > alkyl > alkylthio is valid.The results can be understood in terms of a zwitterionic intermediate 19 or a highly polarized transition state of the rearrangement.