Transformations of hydroxy cyclic sulfates: stereospecific conversion into 2,3,5-trisubstituted tetrahydrofurans.
1,2-Cyclic sulfates have been prepared from O-protected ricinoleate and ricinelaidate esters. Upon deprotection of the 12-hydroxy moiety, the resulting 12-hydroxy-9,10-cyclic sulfates underwent stereospecific cyclization to the corresponding 2,3,5-trisubstituted tetrahydrofurans. The cyclization occurs by backside attack of the hydroxy oxygen on the distal carbon of the 1,2-cyclic sulfate, with inversion at that center.
Kalantar
T H
TH
Department of Chemistry, Massachusetts Institute of Technology, Cambridge 02139.
Sharpless
K B
KB
D004952:Esters; D005663:Furans / Q000138:chemical synthesis*; D012277:Ricinoleic Acids / Q000737:chemistry*; D013464:Sulfuric Acids / Q000138:chemical synthesis* / Q000737:chemistry
D004952:Esters; D005663:Furans; D012277:Ricinoleic Acids; D013464:Sulfuric Acids; C018674:tetrahydrofuran