Scale-Up of a Rh-Catalyzed Asymmetric sp-sp Suzuki-Miyaura-Type Reaction.

Csp-Csp Suzuki-Miyaura couplings (SMCs) are ubiquitous in the synthesis of small molecules, but analogous Csp-Csp bond-forming SMCs are rare, especially asymmetric variants. Recently, we developed a series of Rh-catalyzed couplings between racemic sp-hybridized allyl chlorides and heteroaryl boronic acids. Here, we demonstrate that these catalytic asymmetric reactions can be scaled-up to give over 100 g of a product.

Alcohols as Alkylating Agents in the Cation-Induced Formation of Nitrogen Heterocycles.

A Ti(Oi-Pr) promoted 5- or 6-endo-trig cyclisation to make nitrogen heterocycles is presented. The utilisation of HFIP as a key solvent enables the stereoselective preparation of di- & tri-substituted pyrrolidines and piperidines while forming a new C-C bond at the same time. The process is triggered by a cationic intermediate generated from an allylic or benzylic alcohol and leads to the simultaneous generation of both a C-C and a C-N bond in a single step.