Henry condensation under high pressure 2. Effect of aromatic aldehyde type and pressure on the yield of ?-nitrostyrenes and secondary processes
摘要:
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.
The stereospecific addition of hydroxylamines to α,β-unsaturated sulfones, nitriles and nitro compounds
作者:Ian A O'Neil、Ed Cleator、J.Mike Southern、Jamie F Bickley、David J Tapolczay
DOI:10.1016/s0040-4039(01)01746-4
日期:2001.11
N-Alkyl hydroxylamines have been shown to undergo a highly stereospecific cis addition to α,β-unsaturated sulfones, nitriles and nitro compounds.
N-烷基羟胺已显示出对α,β-不饱和砜,腈和硝基化合物具有高度立体定向的顺式加成作用。
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.
A convenient synthesis and cytotoxic evaluation of β-aryl-α-methylidene-γ-lactones and β-aryl-α-methylidene-γ-lactams
3-Aryl-2-diethoxyphosphoryl-4-nitrohexanoates 8, obtained by Michael addition of ethyl diethoxyphosphorylacetate 6 to 1-aryl-2-nitro-1-butenes 7, were utilized as convenient common intermediates in the synthesis of β-aryl-γ-ethyl-α-methylidene-γ-lactones 17 and β-aryl-γ-ethyl-α-methylidene-γ-lactams 21. Transformation of the nitro functionality in 8 into a hydroxyl or amino group and cyclization yielded lactones 16 or lactams 19, which were used in HornerâWadsworthâEmmons olefination of formaldehyde to give target compounds in good yields. Cytotoxicity of these compounds was evaluated in vitro against mouse leukemia cell line L-1210 and two human leukemia cell lines, HL-60 and NALM-6. Two of the obtained compounds 17b,c with 4-bromophenyl and 4-methylphenyl substituents in the β position proved to be very potent against all three cell lines with IC50 values lower than 6 μM.