Highly regio- and stereoselective intermolecular tandem reaction to synthesize chloro-substituted 1,3-butadienes

Abstract

A palladium catalyzed highly regio- and stereoselective intermolecular tandem reaction of alkynes, CuCl(2) and alkenes by a sequence of chloropalladation/Heck reaction to produce chloro-substituted 1,3-dienes is achieved.

Switch of Selectivity in the Synthesis of α‐Methylene‐γ‐Lactones: Palladium‐Catalyzed Intermolecular Carboesterification of Alkenes with Alkynes

“…(2)]. 4g This result indicates that, in this case, temperature plays a crucial role in the transformation. A competitive reaction occurred when allyl chloride and allyl acetate were used as the terminating coupling reagents.…”

Switch of Selectivity in the Synthesis of α‐Methylene‐γ‐Lactones: Palladium‐Catalyzed Intermolecular Carboesterification of Alkenes with Alkynes

“…[1] In particular, cross-coupling reactions of alkynes and alkenes catalyzed by palladium complexes have been studied extensively, because of the accessibility of reactants and the diversity of products. [2][3][4] One of the major challenges that remain in the nucleopalladation of alkynes is to improve the stereo-and regioselectivities of the nucleopalladation to CÀC triple bonds. Three strategies are typically employed: 1) the concentration of the nucleophiles is increased; [5] 2) one palladated isomer is dominant if it leads to the formation of kinetically more stable structures, that is, aromatic rings; [6] 3) a directing group determines the selectivity.…”

Electrochemical oxidative Z-selective C(sp2)–H chlorination of acrylamides

“…1 Furthermore, Z-chloroacrylic acid derivatives serve as useful building blocks to selectively access ubiquitous Z-configured olefins. 2 Existing synthetic methods to access Z-b-chloroacrylic acid derivatives include Vilsmeier-Haack, 3 Wittig, 4 and chloropalladation/Heck approaches, 5 in addition to hydrochlorination 6 and carbochlorination 7 of alkynes, which somewhat limits the accessible substitution patterns and some of these methods can exhibit poor E/Z selectivity. As such, the development of new synthetic methods that enable the direct and selective access to Z-chloroacrylic acid derivatives is an important and timely goal in organic synthesis.…”