A review with 23 refs. The transition metal catalyzed isomerization reactions of acetylenic derivatives were studied. (E,E)-conjugated dienones, dienoic esters and dienoic amides were synthesized from corresponding a,b-ynones, 2-ynoic esters and 2-ynoic amides, resp. 2-Ynols were first isomerized to the corresponding 2-enones or 2-enals. The reactions can be accomplished simply, in high yield, and stereoselectively. It is proposed that allenic compounds are initially formed as the main intermediates and then isomerized further to the products. A convenient and potential useful methodol. is provided for the preparation of important intermediates in the synthesis of natural products.

Key words: AMIDES, ISOMERIZATION, ESTERS, NATURAL PRODUCTS, ALKYNE P, CATALYSIS, CONJUGATED DOUBLE BOND, ORGANIC SYNTHESIS, TRANSITION METAL COMPOUND, KETENE