Henry condensation under high pressure 2. Effect of aromatic aldehyde type and pressure on the yield of ?-nitrostyrenes and secondary processes
作者:N. E. Agafonov、I. P. Sedishev、A. V. Dudin、A. A. Kutin、G. A. Stashina、V. M. Zhulin
DOI:10.1007/bf00965433
日期:1991.2
Condensation of aromatic aldehydes (I)-(XX) with EtNO2 and n-PrNO2 in AcOH in the presence of AcONH4 or i-BuNH2 gives primarily omega-nitrostyrenes (Ia, b)-(XXa, b) and small quantities of nitriles (Ic)-(XXc), oximes (Id)-(XXd), and ketones (Ie, f)-(XXe, f). The yields of (Ia, b)-(XXa, b) at P = 1 atm are higher for acceptor substituents on the aromatic ring whereas at P = 10 kbar, they are higher for donor substituents. High pressures suppress the formation of (Ic-f)-(XXc-f) and the Z-isomers of (Ia, b)-(XXa, b). The high pressure technique is especially useful in the preparation of donor-substituted (Ia, b)-(XXa, b) which are intermediates in the synthesis of the psychotropic beta-phenylethylamines.