PEPPSI max:KO i Pr被确定为Pd催化硫化的关键成分(参见方案)。钾对于保持较低的硫醇浓度至关重要,而异丙醇对于激活前催化剂和破坏基于硫化钯的静止状态则必不可少。一起与反应性的Pd-PEPPSI-IPent氯 ø甲基吡啶催化剂,该系统耦合深刻在RT失活的合作伙伴,其它催化剂可以在回流的甲苯中未完成。
Mycobacterium tuberculosis β-gentiobiosyl diacylglycerides signal through the pattern recognition receptor Mincle: total synthesis and structure activity relationships
作者:Mark B. Richardson、Shota Torigoe、Sho Yamasaki、Spencer J. Williams
DOI:10.1039/c5cc04773k
日期:——
Gentiobiosyl diglycerides fromMycobacterium tuberculosisare shown to signal through Mincle; structure–activity relationships reveal analogues with enhanced potency.
nest: The first thiocarboxylation of styrenes and acrylates with CO2 to generate important β-thioacids was realized by using visible light as a driving force and catalytic iron salts as promoters. This multicomponentreaction features broad substrate scope, mild reaction conditions, and high regio-, chemo-, and diasteroselectivity. Mechanistic studies indicate that a radical pathway can account for the
yields and excellent regio-, enantio-, and Z/E-selectivities. The utility of this transformation was demonstrated by a broad range of styrenes and 1,3-dienes, facile product modification, and synthesis of bioactive compounds (R)-(-)-curcumene and (S)-(+)-ibuprofen. Mechanistic studies demonstrated the carboxylation of phenylethylcopper complexes with CO2 as one key step.
在此,我们报告了具有 1 个大气压的 CO2 的苯乙烯和 1,3-二烯的高度区域选择性和对映选择性铜催化还原羟甲基化。各种重要的手性高苄醇很容易从苯乙烯制备。此外,各种 1,3-二烯也以高产率和优异的区域选择性、对映选择性和 Z/E 选择性转化为手性高烯丙醇。广泛的苯乙烯和 1,3-二烯、简便的产品改性以及生物活性化合物 (R)-(-)-姜黄烯和 (S)-(+)-布洛芬的合成证明了这种转化的效用。机理研究表明,苯乙基铜配合物与 CO2 的羧化是一个关键步骤。
Mechanism of the reaction of N-p-tosylsulphilimine and related compounds with thiophenolate ion
reaction of alkyl aryl N-p-tosylsulphilimines with thiophenolate ion was found to afford quantitatively the sulphide that arises by an SN2 like reaction on the carbon atom adjacent to the tri-valent sulphur atom. This reaction was also found to proceed smoothly with such compounds as sulphoxides and sulphones and sulphoxmanes. The kinetic study on the reaction between arylmethyl N-p-tosylsulphilimine
发现烷基芳基N-对甲苯磺酰基亚胺与硫酚盐离子的反应定量地提供了由类似于S N 2的反应在邻近三价硫原子的碳原子上产生的硫化物。还发现该反应在诸如亚砜,砜和亚砜基的化合物中可顺利进行。在DMF中对芳基甲基N-对甲苯磺酰亚氨基亚胺与硫酚酸根离子之间反应的动力学研究表明,该反应是二级的,即对于每个硫酚酸根离子和亚硫亚胺而言是一级的。反应的活化焓和熵为ΔH ≠ = -17·kcal / mol和ΔS ≠分别等于-5·7 eu。取代基在反应中的作用-p -XC 6 H 4 +(- SO 2 C 6 H 4 Y- p)CH 3 + p -ZC 6 H 4 SK与Hammettσ值很好相关,得到ϱ x = + 2 ·4,y = + 1·2,z = -1·8。同时,观察到烷基苯基N-对甲苯磺酰亚胺基亚胺中的大体积烷基显着的空间延迟。此外,根据使用旋光秒的反应的立体化学研究-辛基苯基N-对甲苯磺酰亚胺与硫酚