本文描述了一种定义明确的钴(II)半三明治复合物,其带有膦酰氨基配体Cp * Co(1,2-Ph 2 PC 6 H 4 NH)(1),可以活化频哪硼烷(HBpin)作为催化末端烯烃的硼氢化。钴(II)-酰胺基的协同反应1使B-H键断裂,从而得到17电子氢化钴(Cp * Co(1,2-Ph 2 PC 6 H 4 N H(Bpin)),缩写H 1(Bpin),其中硼氮被膦酰氨基配体的未配位氮原子捕获。C═C键的氢硼化可由末端烯烃的β位上的杂原子如N或O促进。这种氢化硼化的机理是通过基于氢化钴(II)的各种化学计量反应确定的。借助Co II – N对B–H键断裂的协同反应,我们的催化依赖于系统自身生成的Co II– H氢化物。
Phospha-Münchnones: Electronic Structures and 1,3-Dipolar Cycloadditions
作者:Daniel J. St-Cyr、Marie S. T. Morin、Francine Bélanger-Gariépy、Bruce A. Arndtsen、Elizabeth H. Krenske、K. N. Houk
DOI:10.1021/jo1008383
日期:2010.6.18
The reaction of imines, acid chlorides, PR3, and base generates a new class of 1,3-dipoles: phospha-Münchnones. These 1,3-dipoles can undergo cycloadditions with alkynes followed by loss of phosphine oxides to form pyrroles. Cycloaddition reactivity is dependent upon the PR3 employed, with PhP(catechyl) (catechyl = o-O2C6H4) providing the most rapid cycloadditions and optimal pyrrole yields. 1H, 13C
亚胺,酰氯,PR 3和碱的反应生成一类新的1,3-偶极子:phospha-Münchnones。这些1,3-偶极子可以与炔烃进行环加成反应,然后损失氧化膦形成吡咯。环加成反应性取决于所采用的PR 3,其中PhP(catechyl)(catechyl = o -O 2 C 6 H 4)提供最快的环加成反应和最佳的吡咯产率。1 H,13 C和311 H NMR分析和计算表明,贫电子的炔丙基取代的亚膦酸酯和亚磷酸酯倾向于环状的1,3-偶极结构,而更多的富电子膦则更倾向于价互变异构的无环基价。X射线晶体学研究证实了这一点。密度泛函理论计算支持由不同PR 3引起的多种P-O相互作用并指出最有效的协同1,3-偶极环加成反应是针对那些其基态几何形状最像过渡态几何形状的偶极子。计算这些偶极子与带有吸电子基团的单取代炔烃的反应是通过逐步机理进行的。磷单元的存在会在1,3偶极子上产生较大的电子偏压,从而允许使
Pd-catalyzed asymmetric allylic alkylations via C–H activation of N-allyl imines with glycinates
作者:Barry M. Trost、Xiaoxun Li
DOI:10.1039/c7sc02899g
日期:——
Herein is reported the first example of palladium-catalyzedasymmetricallylic alkylation (AAA) reactions involving 2-aza-π-allyl palladium intermediates. The 2-aza-π-allyl complex was generated via a novel mode of activation of N-allyl imines. Pd-catalyzed C(sp3)–H activation of N-allyl imines and subsequent nucleophilic attack by glycinates delivered vicinal diamino derivatives as the sole regioisomers
Selective hydrosilylation of N-allylimines using a (3-iminophosphine)palladium precatalyst
作者:Hosein Tafazolian、Joseph A. R. Schmidt
DOI:10.1039/c5cy01859e
日期:——
Hydrosilylation utilizing a (3-iminophosphine)palladium catalyst leads to the selective reduction of the imine unit of allylimines.
利用(3-亚磷腙基)钯催化剂进行氢硅烷基化反应,可以选择性地还原烯丙基亚胺中的亚胺基团。
Nickel(II) Catalyzed Hydroboration: A Route to Selective Reduction of Aldehydes and
<i>N</i>
‐Allylimines
作者:Istiak Hossain、Joseph A. R. Schmidt
DOI:10.1002/ejic.202000092
日期:2020.5.22
[(iminophosphine)nickel(allyl)]+ complex was found to be sufficiently electrophilic to activate aldehydes and N‐allylimines to undergo hydroboration with pinacolborane (HBpin) under mild reaction conditions. The catalyst displayed excellent selectivity toward aldehydes in the presence of ketones. A wide variety of functional groups were tolerated, including halogens, NO2, CN, OMe, and alkenes for both aldehydes
Addition of a B–H Bond across an Amido–Cobalt Bond: Co<sup>II</sup>–H-Catalyzed Hydroboration of Olefins
作者:Maofu Pang、Chengjuan Wu、Xuewen Zhuang、Fanjun Zhang、Mincong Su、Qingxiao Tong、Chen-Ho Tung、Wenguang Wang
DOI:10.1021/acs.organomet.8b00114
日期:2018.5.14
pinacolborane (HBpin) for catalytic terminal hydroboration of olefins. The cooperative cobalt(II)–amido reactivity in 1 enables the B–H bondcleavage, affording the 17-electron cobalt(II) hydride Cp*Co(1,2-Ph2PC6H4NH(Bpin)), abbreviated H1(Bpin), in which the borenium ion is captured by the uncoordinated nitrogen atom of the phosphinoaminato ligand. Hydroboration of the C═C bond can be promoted by a heteroatom
本文描述了一种定义明确的钴(II)半三明治复合物,其带有膦酰氨基配体Cp * Co(1,2-Ph 2 PC 6 H 4 NH)(1),可以活化频哪硼烷(HBpin)作为催化末端烯烃的硼氢化。钴(II)-酰胺基的协同反应1使B-H键断裂,从而得到17电子氢化钴(Cp * Co(1,2-Ph 2 PC 6 H 4 N H(Bpin)),缩写H 1(Bpin),其中硼氮被膦酰氨基配体的未配位氮原子捕获。C═C键的氢硼化可由末端烯烃的β位上的杂原子如N或O促进。这种氢化硼化的机理是通过基于氢化钴(II)的各种化学计量反应确定的。借助Co II – N对B–H键断裂的协同反应,我们的催化依赖于系统自身生成的Co II– H氢化物。