7-Deoxy-7-iodohept-1-enitols react intramolecularly to give 5-carba analogues of pyranoses (pseudo sugars) by the action of tributyltin hydride, which generates a radical at C-7. The configuration at the new chiral centre depends on the relative orientation of the oxygen functions in the starting material and the pattern of substitution.
Synthesis of pseudo-sugars based on desymmetrization of dienylsilanes
摘要:
A synthesis of pseudo-sugars using the desymmetrization of a dienylsilane, followed by a stereocontrolled introduction of the hydroxymethyl group at C5. is described. The CH2OH group at C5 was elaborated using either a regioselective cyclopropane-ring opening or a [2,3]-Wittig rearrangement. (C) 1997 Elsevier Science Ltd.