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Reductive lithiation of 3,5-dimethoxybenzyl methyl ether was successfully performed with lithium wire and a catalytic amount of naphthalene in dry tetrahydrofuran at −15 • C, leading to the quantitative generation of 3,5-dimethoxybenzyllithium. This organometallic compound, which can be stored for at least 24 h, was trapped with a variety of different electrophiles, including, besides aldehydes, non-functionalized and functionalized alkyl halides and an epoxide. Accordingly, it is a useful intermediate in the synthesis of 5-substituted natural and non-natural resorcinols.

Regioselective Reductive Demethoxylation of 3,4,5-Trimethoxystilbenes. -It is found that reduction of 3,4,5-trimethoxystilbenes with Na in THF allows regioselective removal of the 4-methoxy group. Careful control of reaction conditions and quenching method leads to formation of either 3,5-dimethoxystilbenes or 3,5-dimethoxybibenzyls which are of biological interest. -(AZZENA*, U.; DETTORI, G.; IDINI, M. V.; PISANO, L.; SECHI, G.; Tetrahedron 59 (2003) 40, 7961-7966; Dip. Chim., Univ. Sassari, I-07100 Sassari, Italy; Eng.) -Jannicke 04-077

Synthesis of Antibiotic Stilbenes by Reductive Metalation of 3,4,5-Trimethoxybenzaldehyde Dimethyl Acetal. -Naturally occurring trans-stilbenes (VI) and (XIII), which possess antibiotic activity, are prepared via reductive metalation and reaction with suitable electrophiles as the key step. -(AZZENA*, U.; IDINI, M. V.; PILO, L.; Synth. Commun. 33 (2003) 8, 1309-1317; Dip. Chim., Univ. Sassari, I-07100 Sassari, Italy; Eng.) -M. Bohle 36-176