ortho-Metallated complexes of platinum(<scp>ii</scp>) and diplatinum(<scp>i</scp>) containing the carbanions (2-diphenylphosphino)phenyl and (2-diphenylphosphino)-n-tolyl (n = 5, 6)
作者:Martin A. Bennett、Suresh K. Bhargava、Johannes Messelhäuser、Steven H. Privér、Lee L. Welling、Anthony C. Willis
DOI:10.1039/b702808c
日期:——
protonated by HBF4 to form a mu-hydridodiplatinum(II) salt [Pt2(mu-H)(mu-2-C6H4PPh2)2(CNBut)2]BF4 [21]BF4. The J(PtPt) values in [21]BF4 and 18, 2700 Hz and 4421 Hz, respectively, reflect the weakening of the Pt-Pt interaction caused by protonation. Similarly, 16 and 17 react with the electrophiles iodine and strong acids to give salts of general formula [Pt2(mu-Z)(mu-C6H3-5-R-2-PPh2)2(PPh3)2]Y (Y = Z =
当将邻金属化的配合物顺式[Pt(kappa(2)-C6H3-5-R-2-PPh2)2](R = H 1,Me 2)在甲苯中加热或在室温下用CO处理时,四元螯合环之一不可逆地打开,得到双核异构体[Pt2(kappa(2)-C6H3-5-R-2-PPh2)2(mu-C6H3-5-R-2-PPh2)2]( R = H 10,Me 11)。单晶X射线衍射研究显示10中的Pt ... Pt分离为3.3875(4)A。1和2与CO反应的副产物是聚合异构体(R = H 13,Me 14 ),其中一种PC配体被认为在分子间桥接相邻的铂原子。与1和2的行为相反,当在甲苯中加热cis- [Pt(kappa(2)-C6H3-6-Me-2-PPh2)2](cis-3)时,主要产物是反式3 ,顺式3与CO反应生成羰基配合物[Pt(CO)(kappa(1)-C-C6H3-6-Me-2-PPh2)(2-C6H3-6-Me-2-PPh2)]
Ruthenium-Catalyzed Gram-Scale Preferential C–H Arylation of Tertiary Phosphine
arylation of tertiary phosphine ligands catalyzed by a ruthenium(II) complex was devised. This protocol gives access to a series of modified Buchwald–biaryl monophosphines on a gram scale in moderate to excellent yields. A catalytic cycle is proposed derived from knowledge of the intermediates observed by ESI-MS. Importantly, these monoarylated products could be further transformed into dibenzophosphole derivatives
Pd-Catalyzed Asymmetric C–H Bond Activation for the Synthesis of P-Stereogenic Dibenzophospholes
作者:Zhen Li、Zi-Qi Lin、Chao-Guo Yan、Wei-Liang Duan
DOI:10.1021/acs.organomet.9b00216
日期:2019.10.28
Pd-catalyzed asymmetric C–Hbondactivation for the synthesis of P-stereogenic dibenzophospholes was efficiently achieved via two types of catalytic systems. Chiral phosphoric amides/acids as ligands provided the products with up to 5:95 er, and (R)-segphos as ligand resulted in enantioselectivities of up to 98:2.