Palladium-Catalyzed Oxidative Difunctionalization Of Alkenes With α-Carbonyl Alkyl Bromides

The transition metal catalyzed Heck reaction of aryl and vinyl halides with olefins is one of the most efficient carbon-carbon bond-forming coupling reactions. It has become a powerful tool in synthesis and is commonly used in making of drugs,natural products and functional materials.Over the past several years transition-metal-catalyzed difunctionalization of alkenes with organohalides or organometallic reagents has proven to be a reliable tool to obtain diverse difunctionalized products. Despite their importance, few methods initiated by the Heck insertion and especially under oxidative conditions have been reported, and most are restricted to the formation of σ-alkyl palladium(II)intermediates from aryl halides or arylmetallic reagents. Thus, methods utilizing a Heck insertion process are desirable for the oxidative difunctionalization of alkenes with alkyl halides.On the basis of these, this dissertation mainly studies on palladium-catalyzed oxidative difunctionalization of alkenes with α-carbonyl alkyl bromides. The contents of this dissertation are as following:(1) In chapter 1, recent progress in the transition metal catalyzed Heck reactions and palladium-catalyzed difunctionalization of alkenes with organohalides or organometallic reagents has been described in detail. This chapter, including:(i)advances in palladium-catalyzed Heck reactions,(ii) advances in cobalt-catalyzed Heck reactions,(iii) advances in nickel-catalyzed Heck reactions,(iv) advances in other transition metals catalyzed Heck reactions, and(v) palladium-catalyzed difunctionalization of alkenes with organohalides or organometallic reagents. We focus on the results and the mechanisms of the transition metal catalyzed Heck reactions and palladium-catalyzed difunctionalization of alkenes with organohalides or organometallic reagents.(2) In chapter 2, a new palladium-catalyzed oxidative difunctionalization of N-arylalkenes with α-carbonyl alkyl bromides is presented with the addition of Ag2CO3. This transformation includes tandem C-Br/C-H functionalization and intramolecular cyclization to synthsize indolin-2-one structures. This method can be applied to various α-carbonyl alkyl bromides, including primary, secondary, and tertiary α-bromoalkyl esters, ketones, and amides.(3) In chapter 3, an efficient type of palladium-catalyzed oxidative difunctionalization of N-(arylsulfonyl)alkenes with α-carbonyl alkyl bromides for the selective synthesis of acylic and cyclic quaternary stereocenters has been developed and proceeds by 1,4-aryl migration incorporation.