Dioxolane-to-bridged acetal-to-spiroketal via ring-closing metathesis and rearrangement: a novel route to 1,7-dioxaspiro[5.5]undecanes.
Several examples of 1,7-dioxaspiro[5.5]undecane spiroketal systems have been synthesized from the common bicyclic intermediate 1 via acid-catalyzed rearrangement. Intermolecular ketalization of C(2) symmetric diene diol 3 with ketone 9 and then desymmetrization by ring-closing metathesis rapidly constructs bicyclic acetal 1. The locked conformation and steric bias of 1 allow stereoselective functionalization of one or both double bonds before spiroketalization.
Keller
Valerie A
VA
Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, WI 53706-1396, USA.
Martinelli
Joseph R
JR
Strieter
Eric R
ER
Burke
Steven D
SD
D000080:Acetals / Q000737:chemistry*; D000473:Alkanes / Q000138:chemical synthesis* / Q000737:chemistry; D004148:Dioxolanes / Q000737:chemistry*; D008968:Molecular Conformation
D000080:Acetals; D000473:Alkanes; D004148:Dioxolanes; C022884:undecane; C010962:formal glycol