单晶变角EPR谱的解释Ⅱ.掺Cr3+乙酰丙酮铝单晶的EPR

对掺Cr³⁺乙酰丙酮铝单晶的(001),(100)和(110)晶面进行晶面旋转EPR扫描,得到共振磁场随旋转角度变化的实验图形,根据本征插方法编写的程序,对实验谱图进行投合,得到下述顺磁参数,D=0.5870±O.005cm^-1,E=-0.00490±0.0001cm^-1,g_x=g_y=1.965±0.001,g₂=1.984±0.001.     

配位体对铑催化低压羰基合成的影响(Ⅱ)——几种有机磷和亚磷酸酯配位体的比较

本文分别以三(对甲基苯基)膦,亚磷酸三(对甲基苯基)酯,亚磷酸三(对氯苯基)酯,亚磷酸三(邻甲氧基苯基)酯,亚磷酸三苯基酯等为配位体,以二羰基乙酰丙酮铑为催化剂母体,研究1—庚烯醛化反应的动力学和反应产物的分布,用动力学结果和测得的催化剂体系的红外光谱羰基伸缩振动频率与文献[1]结果比较,进一步说明烯醛化反应的速率不仅决定于其反应的控制步骤,而且与反应体系中活化络合体的浓度有关.亚磷酸三(3,4-二甲基苯基)酯有利于活化络合体的形成,其作为配位体时,醛化反应的速率较其它配位体高得多,同时由于其较大的立体化学效应,提高了对产物中直链醛的选择性.     

THE SYNTHESIS OF PHOSPHORAMIDOTHIOATES AND THEIR QUANTITATIVE STRUCTUREACTIVITY CORRELATIONS

O-Aryl O-ethyl N-isopropyl phosphoramidothioates (Ⅰ) have herbicidal activity. In order to study the relationship between structures and activities of these compounds, more than thirty compounds (Ⅰ) have been prepared by the reaction of O-aryl O-ethyl phosphorochloridothioates with isopropylamine in the presence of 40% NaOH at 0℃. The intermediates, phosphorochloridothioates, were prepared separately from a large excess of O-ethyl Phosphorodichloridothioate and various substituted phenols in the presence of 40% NaOH and a catalyrical amount of Et_3N at 0—5℃. As a result, higher purity and good yields were obtained.It was found that the activity of these compounds was highly dependent upon the substituents attached to the benzene ring with respect to the characteristic parameters π, E_s, σ and F by using Hansch's equation.It was indicated that hydrophobic (π), steric (E_s), and electronic (σ and F) effects of the substituents on the ring in those molecules seem to be of considerable importance i     

双-α-苯甲酰苯乙酮螯合环戊二烯基铕的~1H核磁共振谱

对(C_6H_5COCHCOC_6H_5)_6Eu·OCOCH_3,和 C_5H_5Na反应形成的(C_6H_5COCHCOC_6H_5)_2EuC_5H_5进行了~1H核磁共振谱的测定,结果表明此化合物的分子结构式应为(C_6H_5COCHCOC_6H_5)_2Eu,即环戊二烯基与金属铕间以σ键相连.