Total Syntheses of Menisporphine and Daurioxoisoporphine C Enabled by Photoredox-Catalyzed Direct C–H Arylation of Isoquinoline with Aryldiazonium Salt
作者:Jing Zhang、Jie Chen、Xiaoyun Zhang、Xiaoguang Lei
DOI:10.1021/jo5020432
日期:2014.11.7
due to their diverse chemical structures as well as remarkable bioactivities. Herein, we report the concise total syntheses of two isoquinoline alkaloids, menisporphine and daurioxoisoporphine C, through a mild and efficient photoredox-catalyzed direct C–H arylation of isoquinoline core with aryldiazonium salt. This new strategy is complementary to the conventional isoquinoline synthesis and would provide
Palladium-Catalyzed Cross-Coupling of Aryl Halides Using Organotitanium Nucleophiles
作者:Hang Wai Lee、Fuk Loi Lam、Chau Ming So、Chak Po Lau、Albert S. C. Chan、Fuk Yee Kwong
DOI:10.1002/anie.200904033
日期:2009.9.21
couple: Catalysts generated from Pd(OAc)2 and indolylphosphine ligands are highly effective in the titanium‐mediated coupling of arylhalides. Catalyst loadings as low as 0.05 mol % Pd can be used. The mild reaction conditions also allow the coupling of aryl sulfonyl chlorides with aryl titanium reagents to generate diaryl sulfones.
Cobalt-Catalyzed Cross-Coupling Reactions of Heterocyclic Chlorides with Arylmagnesium Halides and of Polyfunctionalized Arylcopper Reagents with Aryl Bromides, Chlorides, Fluorides and Tosylates
A range of aromatic organocopper or organomagnesium compounds undergo smooth cross-coupling reactions with aryl bromides, chlorides, fluorides and tosylates, leading to polyfunctionalized aromatics or heterocycles in the presence of cobalt salts (5-7.5 mol%) as catalysts. Very mild reaction conditions are needed and, in the case of cross-coupling with organocopper compounds, Bu4NI (1 equiv) and 4-fluorostyrene (20 mol%) are essential as promoters for successful couplings.
New Cobalt-Catalyzed Cross-Coupling Reactions of Heterocyclic Chlorides with Aryl and Heteroaryl Magnesium Halides
作者:Paul Knochel、Tobias J. Korn、Gérard Cahiez
DOI:10.1055/s-2003-41460
日期:——
New cobalt-catalyzed cross-coupling between arylmagnesium halides and 2-chloropyridines and related heterocycles occur at low temperature leading to 2-arylated heterocycles in good yields.
Asymmetric hydrogenation: The title reaction provides an efficient and rapid access to chiral 1‐ and 3‐substituted 1,2,3,4‐tetrahydroisoquinolines with excellent enantioselectivity (see scheme; L=ligand). A preliminary mechanistic study indicates that the 1,2‐hydride addition might be the initial step in the reaction. The method has been used in the synthesis of urinary antispasmodic drug (+)‐solifenacin
不对称氢化:标题反应可高效且快速地获得手性1和3-取代的1,2,3,4-四氢异喹啉,且具有出色的对映选择性(参见方案; L =配体)。初步的机理研究表明,添加1,2-氢化物可能是反应的第一步。该方法已用于尿解痉药(+)-索非那新的合成。