Boron trihalide-promoted addition of aryl aldehydes to styrenes. A new convenient and highly efficient synthesis of 1,3-dihalo-1,3-diarylpropanes
作者:George W Kabalka、Zhongzhi Wu、Yuhong Ju
DOI:10.1016/s0040-4039(01)01125-x
日期:2001.8
Reactions of aryl aldehydes with styrenes in the presence of borontrichloride in CH2Cl2 at 0°C produce 1,3-dichloro-1,3-diarylpropanes in excellent yields. Reactions carried out using boron tribromide generate the corresponding 1,3-dibromo-1,3-diarylpropane in good yields.
Synthesis of 4,5-Dihydroisoxazoles from Arylcyclopropanes and Nitrosyl Chloride
作者:O. B. Bondarenko、A. Yu. Gavrilova、L. G. Saginova、N. V. Zyk
DOI:10.1023/b:rujo.0000003196.89457.a4
日期:2003.7
Arylcyclopropanes readily react with nitrosyl chloride in liquid sulfur dioxide to give the corresponding 5-aryl-4,5-dihydroisoxazoles in good yield. The reaction is most selective at -40 to -50degreesC; at higher temperature, the contribution of side processes becomes appreciable. The complete conversion of arylcyclopropanes containing donor substituents is attained with the use of 1.5 equiv of nitrosyl chloride, while the rate of the transformation of compounds with nonactivated aromatic rings considerably increases on raising the molar ratio NOCl-arylcyclopropane.