Stabilization of a simple enol, 2-methylprop-1-en-1-ol by triphenylphosphinerhodium(I) complexes

Article abstract of DOI:10.1016/0022-328X(88)83127-9

The rhodium(I) complexes, ClO4 (1), ClO4 (5), Rh(ClO4)(CO)(PPh3)2 (6) and Rh(ClO4)(CO)(AsPh3)2 (7) catalyze the isomerization of 2-methylprop-2-en-1-ol (3) to give 2-methylpropanal (4) at room temperature under nitrogen.During the isomerization (3 -> 4), a large amount of the simple enol 2-methylprop-1-en-1-ol (2) was formed in the presence of 1, but a somewhat lesser amount of 2 was formed in the presence of 6.The rate of double bond migration (3 -> 2) is greater in the presence of 6 than in the presence of 1.A small amount of 2 was detected in the presence of 7 whereas no enol (2) was formed in the presence of 5.