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The use of the Barbier-Grignard reaction, where premixed allyl bromide and the carbonyl compound are added to magnesium in ether, is reported for the synthesis of homoallylic alcohols. This reaction provides good to excellent yields of most homoallylic alcohols with minimal formation of Wurtz coupling products. [ABSTRACT FROM AUTHOR]

A [10,10]paracyclophane, 5,5,6,6,21,21,22,22-octamethyl-5,6,21,22-tetragerma[10.10]paracyclophane (4a), with two &z.sbnd;R1R2GeGeR1R2&z.sbnd; moieties in the center of two bridges, was prepared. An attempt to synthesize cyclophanes, 4b (R1=Me; R2=Ph) and 4c (R1=R2=Ph) was also made. The products were not analytically pure even after strenuous purification procedure to indicate that a double Wurtz coupling reaction is extremely difficult and necessarily accompanied by formation of polymeric by-products. [Copyright &y& Elsevier]