Palladium-Catalyzed Highly Diastereoselective Cyclic Carbopalladation−Carbonylative Esterification Tandem Reaction of Iododienes and Iodoarylalkenes
摘要:
[GRAPHICS]Pd-catalyzed reaction of iododienes and iodoarylalkenes represented by 1, 8, and 10 under 1 atm of CO and a small amount of O-2 in the presence of a base, e.g., NEt3 as well as MeOH and H2O in DMF can undergo a highly diastereoselective cyclic carbopalladation-carbonylative esterification tandem process (Type II C-Pd process) to give in high yields the corresponding ester-containing cyclization products, e.g., 2, 9, and 11, in as high as 98% diastereoselectivity.
Base-Induced Radical Carboamination of Nonactivated Alkenes with Aryldiazonium Salts
作者:Stephanie Kindt、Karina Wicht、Markus R. Heinrich
DOI:10.1021/acs.orglett.5b03143
日期:2015.12.18
transition-metal-free version of the Meerweinarylation has been developed. The key feature of this carboamination-type reaction is the slow base-controlled generation of arylradicalsfrom aryldiazonium tetrafluoroborates, so that a sufficient quantity of diazonium ions remains to enable efficient trapping of the alkyl radical adduct resulting fromarylradical addition to the alkene. Under strongly
Study on the total synthesis of velbanamine: Chemoselective dioxygenation of alkenes with PIFA via a stop-and-flow strategy
作者:Huili Liu、Kuan Zheng、Xiang Lu、Xiaoxia Wang、Ran Hong
DOI:10.3762/bjoc.9.113
日期:——
5-hydroxymethyl-gamma-lactones were constructed after hydrolysis. This strategy also differentiates terminally substituted alkenes and constitutes a potentially novel synthetic approach for the efficient synthesis toward velbanamine.
In this study, the heterogeneously catalyzed alkoxycarbonylation of olefins with CO2 based on a supported ionic-liquid-phase (SILP) strategy is reported for the first time. An [Ru]@SILP catalyst was accessed by immobilization of ruthenium complex on a SILP, wherein imidazolium chloride was chemically integrated at the surface or in the channels of the silica gel support. An active Ru site was generated
Ruthenium- and rhodium-catalyzed intramolecular C–H/olefin coupling reactions of 1-(2-pyridyl)-, 1-(2-imidazolyl)-, and 1-(2-oxazolyl)-1,5-dienes proceeded in a regiospecific manner to give 5-membe...
Oxidative Catalysis Using the Stoichiometric Oxidant as a Reagent: An Efficient Strategy for Single-Electron-Transfer-Induced Tandem Anion-Radical Reactions
Oxidative single‐electrontransfer‐catalyzed tandem reactions consisting of a conjugate addition and a radical cyclization are reported, which incorporate the mandatory terminal oxidant as a functionality into the product.