Selective Nickel- and Manganese-Catalyzed Decarboxylative Cross Coupling of Some α,β-Unsaturated Carboxylic Acids with Cyclic Ethers

Abstract

A nickel- and manganese-catalyzed decarboxylative cross coupling of α, β-unsaturated carboxylic acids with cyclic ethers such as tetrahydrofuran and 1, 4-dioxane was developed. Oxyalkylation was achieved when nickel acetate was used as catalyst, while manganese acetate promoted the reaction of alkenylation.

An Unexpected Controlled New Oxidant: SO4.–

“…Na 2 S 2 O 4 is an effective reagent for the reduction of aldehydes and ketones to the corresponding alcohols 22 . As a continuation of our research on TBHP and Na 2 S 2 O 4 19 20 21 23 , in a accidental opportunity, we found that TBHP/Na 2 S 2 O 4 can oxidize aromatic alcohols to corresponding aldehydes without any acid formation.…”

Transition-Metal-Free C(sp3)–H Hydroxylation of 2-Oxindoles with Peroxides via Radical Cross-Coupling Reaction in Water

“…Based on above mechanistic studies and the related reported work, ,,− a probable reaction mechanism is presented in Scheme . First, R 4 OOH is split into R 4 O radical and OH radical. ,,− Next, the R 4 O radical abstract a hydrogen atom from 2-oxindole 1 to afford alkyl radical A . − Finally, radical A cross-couples with OH radical to form the desired hydroxylation product 3 . , …”

Manganese-Mediated Coupling Reaction of Vinylarenes and Aliphatic Alcohols

“…Palladium, nickel and copper and other transition metals have been widely studied in functionalization of C-H bonds because of their promise as highly efficient catalysts, but rare examples of Mn-catalyzed C-H activation reactions have been reported 46 47 48 49 50 . The effect of this non-expensive and readily available catalyst in difunctionalization of vinylarenes is still unclear.…”