Infrared spectroscopic and conformational studies of trisubstituted ureas containing chlorophenyl groups
作者:Yoshiuki Mido、Chizuko Furusawa
DOI:10.1016/0022-2860(82)85229-0
日期:1982.6
trans — cis isomerism about the NH-CO rotational axis is discussed in relation to the steric effect of the R 2 group, Ph-Ph interaction and inter- and intra-molecular hydrogen bonding. In dilute solution, R 2 UPhCl exists in the trans or the out form, and RPhUPhCl in the cisform o -Chlorophenyl derivatives show a monomeric v (N-H) band at a wavenumber lower than that of the other derivatives and no
摘要 为了检验引入的氯原子的影响,研究了含有氯苯基的三取代脲 R 2 UPhCl 和 RPhUPhCl [U = NC(O)NH] 在 ν(NH) 区域的红外光谱。围绕 NH-CO 旋转轴的反-反-顺异构现象与 R 2 基团的空间效应、Ph-Ph 相互作用以及分子间和分子内氢键有关。在稀溶液中,R 2 UPhCl 以反式或反式存在,而顺式 RPhUPhCl 邻氯苯基衍生物在波数低于其他衍生物的波数处显示出单体 v (NH) 带,并且没有相关联的 v (NH) ) 在浓溶液或什至在饱和溶液中的条带。
A New Synthesis of Ureas. IV. The Preparation of Unsymmetrical Ureas from Carbon Monoxide, Sulfur, and Amines
作者:R. A. Franz、Fred Applegath、F. V. Morriss、Fred Baiocchi、L. W. Breed
DOI:10.1021/jo01059a049
日期:1962.12
Synthesis of unsymmetrical phenylurea derivatives via oxidative cross coupling of aryl formamides with amines under metal-free conditions
A direct transformation of N-aryl formamides to the corresponding phenylurea derivatives via the formation of isocyanate intermediates is achieved in good yields using hypervalent iodine reagents as external oxidants.