Reductive Generation of Aldehyde Metal Enolate from Ketene. A One-Flask Process to 1,1,2- and 1,2,2-Trisubstituted Dihydronaphthalenes from 1- and 2-Naphthalenecarboxylates

Article abstract of DOI:10.1021/jo00295a005

Successive treatment of 2,6-di-tert-butyl-4-(methoxyphenyl)-1- and -2-naphthalenecarboxylates (BHA esters) (1, 2) with organolithium in THF, lithium triethylborohydride in refluxing THF, methyl iodide-HMPA, and finally sodium borohydride in MeOH provided regio- and stereoselectively 1,1,2- and 1,2,2-trisubstituted dihydronaphthalenes (3, 4), respectively, in good yields.This one-flask process is constituted from a sequence of five reactions involving reductive generation of aldehyde metal enolate from ketene as a key step.