Tetrahedron

Generation of allylic and benzylic organolithium reagents from the corresponding ester, amide, carbonate, carbamate and urea derivatives

E Alonso, D Guijarro, P Martínez, DJ Ramón, M Yus

Index: Alonso, Emma; Guijarro, David; Martinez, Pedro; Ramon, Diego J.; Yus, Miguel Tetrahedron, 1999 , vol. 55, # 36 p. 11027 - 11038

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Citation Number: 37

Abstract

The reaction of different allylic and benzylic non-enolisable esters or amides (1), carbonates (4), carbamates (6, 7) and ureas (8) with an excess of lithium powder and a catalytic amount of naphthalene (10%) in the presence of an electrophile [iPrCHO, tBuCHO, PhCHO, Me2CO, Et2CO,(CH2) 5CO, Ph2CO, Me3SiCl] in THF at different temperatures (− 78,− 30 or 0° C) leads, after hydrolysis with water, to the corresponding allylated or benzylated products (2).

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