130158-49-5Relevant academic research and scientific papers
General stereoselective synthesis of (E)-exo-alkylidene tetrahydrofurans via base-mediated cyclization of hydroxyl propargylic sulfones
Dai, Wei-Min,Lee, Mavis Yuk Ha
, p. 12497 - 12512 (2007/10/03)
The base-promoted cyclization of a number of phenyl propargylic sulfones possessing a β-hydroxyl group afforded 5-substituted (E)-2- [(benzenesulfonyl)methylene]tetrahydrofurans 3 in >80% yield. The phenyl allenic sulfone, formed by isomerization of the phenyl propargylic sulfone under the basic conditions, is attacked by the internal alkoxide to give an allylic anion which undergoes protonation to form the conjugated exo double bond.
Stereoselectivity in the sigmatropic rearrangement of eight- and nine-membered cyclic allylsulfonium ylides. Synthesis of vinyl- substituted butyro- and valerolactones
Kido, Fusao,Sinha, Subhash C.,Abiko, Toshiya,Watanabe, Masataka,Yoshikoshi, Akira
, p. 4887 - 4906 (2007/10/02)
The rhodium (II) acetate-catalyzed [2,3]sigma-tropic rearrangement of the diazo malonates of (z)-4-phen-ylthio-2-buten-1-ol derivatives 6 afforded vinyl-substituted butyrolactones 10 in a highly stereoselective manner, while the rearrangement of the diazo malonates of homologues, (z)-5-phenylthio-3-penten-1-ol derivatives 9, yielded vinyl-substituted valerolactones 13 and 14 in the predominance of the formers. A stereochemically fixed substituent R in 9 was found to be an important factor resulting to high stereoselectivity in the latter rearrangement as shown by using diazo malonate 20b as substrate.
