The expedient and regioselective metalation of unprotected biphenyl-2-, -3-, and -4-carboxylic acids
Unprotected biphenyl-2-carboxylic acid can be cleanly metalated with sec-butyllithium at the position adjacent to the carboxylate and can then be subjected to site-selective electrophilic substitution. The remote C2′-position is attacked by the superbasic
Tilly, David,Samanta, Subhendu S.,Castanet, Anne-Sophie,De, Asish,Mortier, Jacques
ortho-Substituted-2-biphenyl carboxylic acids of the type 3a-j were prepared by the tandem metalation sequence from 2-biphenyl carboxylic acid 1 with sec-butyllithium in THF at -78°C followed by quenching with electrophiles. The carboxylic acids 3a-f were converted into 1-substituted fluorenones 4a-f upon treatment with methanesulfonic acid.
Tilly, David,Samanta, Subhendu S,Faigl, Ferenc,Mortier, Jacques
p. 8347 - 8350
(2007/10/03)
More Articles about upstream products of 500905-09-9