Synthesis of unsaturated esters and lactone from butadiene and carbon dioxide

摘要

Octadienyl esters of 2-ethylidene-hepta-3,5-dienoic and 2-vinyl-hepta-3,5-dienoic acids of formula C8H11COOC8H13 and delta -lactone of formula (II) or 2-ethylidene-hepta-6-ene-5-olide, are prepared by reaction of 1,3-butadiene with CO2 at a temperature comprised between about 20 DEG and 150 DEG C. and at a total pressure between about 10 and 500 atm in the presence of a phosphinic complex of palladium having the formula Pd[P(R)3]x, wherein x is an integer from 2 to 4, and (R)3 is a homogeneous or heterogeneous group consisting of alkyls, cycloalkyls having up to 8 carbon atoms and of phenyls, also substituted, in an inert atmosphere.