jo020169q_si_001.pdf (922.4 kB)
Palladium-Catalyzed Cross-Alkynylation of Aryl Bromides by Sodium Tetraalkynylaluminates
journal contribution
posted on 2002-08-15, 00:00 authored by Dmitri Gelman, Dmitry Tsvelikhovsky, Gary A. Molander, Jochanan BlumSodium tetraalkynylaluminates (1−4), prepared from NaAlH4 and terminal alkynes, cross-couple
with aryl bromides in the presence of Pd(0) and Pd(II) catalysts. The reactions take place in boiling
THF or DME. The process is applicable to both homo- and heterocyclic aryl bromides and can be
used for conversion of polybromo compounds into polyalkynes. The reactions are high yielding and
selective, free of undesired homocoupling and hydrogenolysis processes. The reagents selectively
react with the ring-bound bromine atoms but do not affect chloro, cyano, triflate, or ester functions.