Synthesis of isomeric benchrotrenic alkenes by Ti-induced carbonyl coupling reaction
摘要:
The benchrotrenic ketones BctCOR (1) (Bct: Cr(CO)3C6H5; R = CH3 (a), C2H5 (b), n-C3H7 (c), n-C4H9 (d)) undergo reductive alkene coupling reaction when treated with TiCl3/Li. The two isomeric forms of Bct(R)C=C(R)Bct (2) were isolated in the ratio Z/E = ca. 3:1. Decomplexation of 2 by iodine gave quantitatively the corresponding isomeric alkyl stilbenes C6H5(R)C=C(R)C6H5 (3).