96254-30-7Relevant academic research and scientific papers
Allene C(sp2)-H Activation and Alkenylation Catalyzed by Palladium
Aouane, Fran?oise A.,Baik, Mu-Hyun,Carreira, Erick M.,Schreib, Benedikt S.,Son, Mina
, p. 21705 - 21712 (2022/01/03)
The selective transition-metal-mediated activation of C(sp2)-H bonds of allenes is a formidable challenge because of the competitive, intrinsic reactivity of cumulated double bonds. Herein, we report a Pd-catalyzed C-H alkenylation of electronically unbiased allenes, affording penta-1,2,4-triene products in up to 94% yield. A picolinamide directing group enables the formation of putative allenyl-palladacycles, which subsequently participate in a turnover-limiting Heck-type reaction with electron-deficient alkene coupling partners. This mechanistic proposal is consistent with experimental and computational investigations. Additionally, we report for the first time the use of picolinamide N,O-acetals as readily removable auxiliaries for C-H activation reactions, allowing the efficient alkenylation of allenyl carbinol derivatives. Successful removal of the directing groups without affecting the reactive penta-1,2,4-triene substructure of the products is demonstrated.
CONVENIENT SYNTHESIS OF (TRIPHENYL)GERMYL AND (TRIPHENYL)STANNYL SUBSTITUTED ALLENES
Ruitenberg, K.,Westmijze, H.,Kleijn, H.,Vermeer, P.
, p. 227 - 234 (2007/10/02)
Allenyl-germanes and -stannanes, Ph3MC(R)=C=CR'R" (M = Ge, Sn) can be obtained, generally in excellent yield, through alkylcopper(I)-induced 1,3-substitution of the propargylic chlorides Ph3MCCCR'R"Cl.In the tin series, however transmetallation is the
