444804-99-3Relevant academic research and scientific papers
Synthesis of medium-ring lactones via tandem methylenation/Claisen rearrangement of cyclic carbonates
Anderson, Edward A,Davidson, James E.P,Harrison, Justin R,O'Sullivan, Paul T,Burton, Jonathan W,Collins, Ian,Holmes, Andrew B
, p. 1943 - 1971 (2007/10/03)
The conversion of vinyl-substituted 6- and 7-membered cyclic carbonates into 8- and 9-membered medium-ring lactones has been achieved in good yield using dimethyltitanocene in toluene at reflux. The reaction proceeds by initial formation of a ketene acetal which undergoes subsequent in situ Claisen rearrangement to provide the corresponding lactones. The preparation of the cyclic carbonates is carried out under basic conditions and hence this methodology complements our existing selenium-based methodology for the synthesis of medium-ring lactones.
Enantioselective synthesis of alkyl-substituted eight-membered lactones by Claisen rearrangement
Harrison, Justin R.,Holmes, Andrew B.,Collins, Ian
, p. 972 - 974 (2007/10/03)
The Claisen rearrangement of alkenyl-substituted ketene acetals (produced in situ by selenoxide elimination from the corresponding phenylselenoacetaldehyde-derived acetals of enantiomerically pure 1,3-diol derivatives) afforded unsaturated eight-membered lactones with control of stereochemistry of methyl substituents at C-4, C-5 and C-7, as well as a fused system.
