Preferential formation of five-membered rings in two Claisen cyclisations
摘要:
Alpha-Lithiations of the acetoxy groups of 1 and 2 lead to Claisen cyclisations in which five-membered rings are formed much faster than six-membered rings; this selectivity is opposite to that of aldol condensations.
Alpha-Lithiations of the acetoxy groups of 1 and 2 lead to Claisen cyclisations in which five-membered rings are formed much faster than six-membered rings; this selectivity is opposite to that of aldol condensations.