scaffolds—ortho‐orientated terphenyls presenting twoatropisomeric Ar–Ar axes. These unusual structures were built up by using the C−Hactivation approach, and remarkably, both chiral axes were controlled with excellent stereoselectivity in a single transformation. During the reaction, not only does atroposelective functionalization of a biaryl precursor occur to establish one stereogenic axis, but an
Dibenzyl amine compounds and derivatives, pharmaceutical compositions containing such compounds and the use of such compounds to elevate certain plasma lipid levels, including high density lipoprotein-cholesterol and to lower certain other plasma lipid levels, such as LDL-cholesterol and triglycerides and accordingly to treat diseases which are exacerbated by low levels of HDL cholesterol and/or high levels of LDL-cholesterol and triglycerides, such as atherosclerosis and cardiovascular diseases in some mammals, including humans.
Novel binuclear manganese(III), cobalt(III) and chromium(III) complexes for the alternating ring-opening copolymerization of cyclohexene oxide and maleic anhydride
mononuclear and binuclearmanganese(III), cobalt(III) and chromium(III) complexes have been designed, synthesized and applied to the alternating ring-opening copolymerization of cyclohexene oxide and maleic anhydride with the optimized conditions. Experimental results show that these complexes are effective in the catalytic copolymerization. Among the six complexes, the binuclearcomplexes exhibited better
摘要设计,合成了几种不对称的席夫碱单核和双核锰(III),钴(III)和铬(III)配合物,并在优化条件下将其用于环己烯氧化物和马来酸酐的交替开环共聚。实验结果表明,这些配合物在催化共聚中是有效的。在六个复合物中,双核复合物在相同条件下显示出比单核复合物更好的催化活性。当使用双核铬(III)配合物,然后是锰(III)配合物和二价锰(III)配合物时,共聚物的最高分子量(24,600 g mol-1)具有窄的多分散性(1.07)和较高的单体转化率(95%)。钴(III)配合物在相同条件下显示出相对较低的活性。
Catalytic Enantioselective Alkylation of Aldehydes by Using Organozinc Halide Reagents
enantioselective addition to aldehydes by using a titanium(IV) catalyst derived from a H8‐binaphthol derivative in the presence of [Ti(OiPr)4] and MgBr2. A range of functionalities, including olefin, chlorine atoms, protected alcohols, amides, and cyano groups, are tolerated in the present reaction, providing the corresponding functionalized alcohols in high yields and enantioselectivities (see scheme)
在[Ti(O i Pr)4 ]和MgBr 2存在下,使用衍生自H 8-联萘酚衍生物的钛(IV)催化剂,可以将官能化的烷基卤化锌用于醛的对映选择性加成反应。在本反应中可以耐受多种官能团,包括烯烃,氯原子,受保护的醇,酰胺和氰基,从而以高收率和对映选择性提供相应的官能化醇(参见方案)。
Cobalt-Catalyzed Electrophilic Amination of Aryl- and Heteroarylzinc Pivalates with <i>N</i>
-Hydroxylamine Benzoates
作者:Yi-Hung Chen、Simon Graßl、Paul Knochel
DOI:10.1002/anie.201710931
日期:2018.1.22
Aryl‐ and heteroarylzincpivalates can be aminated with O‐benzoylhydroxylamines at 25 °C within 2–4 h in the presence of 2.5–5.0 % CoCl2⋅2 LiCl to furnish the corresponding tertiary arylated or heteroarylated amines in good yields. This electrophilicamination also provides access to diarylamines and aryl(heteroaryl)amines. A new tuberculosis drug candidate (Q203) was prepared in six steps and 56 %