Mesomorphic Characteristics of Liquid Crystalline Esters<i>p</i>-Methoxyphenyl<i>p</i>-Alkoxycinnamates
作者:Jayrang S. Dave、K. P. Dhake
DOI:10.1246/bcsj.65.559
日期:1992.2
The newly synthesized homologous series p-methoxyphenyl p-alkoxycinnamates (I) can be compared with the series N-[p-(p-alkoxycinnamoyloxy)benzylidene] p-anisidines (II).1) All the homologues of both the series (I) and (II) from C1 to C18 are mesogens. In series (II) the first five members decompose due to high transitions at about 300 °C. With decrease in length of the molecules of series (I) than that of series (II), the overall transitions also decrease by about 150 °C. The first seven members in series (II) are nematogens; polymesomorphism begins from octyloxy homologue with the commencement of smectic mesophase and continues to be exhibited upto the last i.e. octadecyloxy homologue. In series (I) also the nematic phase is exhibited upto the heptyl derivative; the smectic phase commences from C8-member in the form of monotropic phase thereby exhibiting polymesomorphism upto the C14 homologue. The last two members of series (II) are smectogens. The odd-even effect is missing in series (II) whereas in series (I), it is seen upto the fifth homologue. In both the series, the N-I curves show a falling tendency— a criterion of high melting series. From textures’ point of view both the series have common features, the nematic phase is threaded when it is the only mesophase shown and homeotropic in polymesomorphic region, whereas the smectic mesophase is focal conic fan shaped of smectic-A variety. This series also yields interesting comparison with the series (III) p-nitrophenyl p-alkoxycinnamates4) and (IV) p-chlorophenyl p-alkoxycinnamates.5)
Influence of Electronically and Sterically Tunable Cinnamate Ligands on the Spectroscopic Properties and Reactivity of Bis(triphenylphosphine)platinum(0) Olefin Complexes
作者:Magnus R. Buchner、Bettina Bechlars、Bernhard Wahl、Klaus Ruhland
DOI:10.1021/om301021j
日期:2013.3.25
ester)platinum(0) complexes were synthesized to examine electronic and steric influences on their behavior as inhibited precatalysts and to correlate this with 1H, 13C, 19F, 31P and 195Pt NMR spectroscopic, IR spectroscopic, and X-ray structural properties (9 X-ray structures included). The substituent at the 4-position of the phenyl group proved to be a valuable moiety in controlling the electronic properties
总共合成了48种新的双(三苯基膦)(肉桂酸酯)铂(0)配合物,以研究电子和空间位阻对其作为受抑制前催化剂的行为的影响,并将其与1 H,13 C,19 F,31 P和195 Pt NMR光谱,IR光谱和X射线结构特性(包括9个X射线结构)。事实证明,苯基4位上的取代基是控制烯烃配体电子特性以及控制金属-配体键强度的重要部分。反应性和NMR光谱数据与该取代基的Hammett参数相关:尤其是偶联常数2 J PP和1 J PPt。配合物的反应性是通过三苯膦的NMR滴定法(1 H NMR;触发配体取代)以及与二苯基硅烷的反应(1 H和29 Si NMR;触发氧化加成)确定的。所确定的平衡与烯烃的电子密度相关。作为一个典型的例子,可以从配合物的NMR 2 J PP偶合常数间接预测反应性,这也可以从相关的Pd配合物中发现。
PERFUME PRECURSOR
申请人:Takasago International Corporation
公开号:EP3689849A1
公开(公告)日:2020-08-05
The present invention relates to a perfume precursor represented by formula (1). (In formula (1), R1 represents a hydrogen atom, a C1-C12 alkyl group, a hydroxy group, a methoxy group, or an ethoxy group; R2 represents a single bond, a C1-C2 alkylene group which may have a substituent, or a vinylene group which may have a substituent; R3 represents a residue obtained by removing one hydrogen atom of a hydroxy group from a C5-C20 perfume alcohol or a phenol which may have a substituent.)