Ni-Catalyzed Coupling of Butadiene, Aldimines, and Arylboronic Acids to Homoallylic Amines under Base-Free Conditions

Understanding mechanism driven regioselectivity in zirconium-catalysed hydroaminoalkylation: homoallylic amines from conjugated dienes

The unexpected 4,1-hydroaminoalkylation of dienes provides selective access to linear homoallylic amines by zirconium catalysis. This switch from the traditional branched preferred regioselectivity to selective linear product formation using this early transition metal can be attributed to π-allyl intermediates. The reactivity of these isolated intermediates on a sterically accessible and coordinatively flexible chelating bis(ureate) Zr(iv) complex confirmed reversible C-C bond formation in hydroaminoalkylation catalysis.

Approach to the Synthesis of gem-Thiolated Alkylboronates via Cobalt-Catalyzed Diboration of Aldehydes

A new method has been developed for the sequential gem-thioborylation of readily available aldehydes via the cobalt-catalyzed diboration reaction. The N-heterocyclic carbene (NHC)-cobalt complex has been used as a catalyst for the diboration of aldehydes to generate α-oxyl boronic esters, which react with lithium thiolates to form a tetracoordinate boronate species, which undergoes 1,2-metalate rearrangement in the presence of trifluoroacetic anhydride. The stepwise functionalization of the boryl and thiol moiety of the products enriches the chemical toolbox of diverse organic synthesis.

Ni-catalyzed arylation of alkynes with organoboronic acids and aldehydes to access stereodefined allylic alcohols

A new, efficient and practical method for the three-component arylative coupling of aldehydes, alkynes and arylboronic acids has been developed through nickel catalysis. This transformation provides diverse Z-selective tetrasubstituted allylic alcohols without the use of any aggressive oragnometallic nucleophiles or reductants. Moreover, benzylalcohols are viable coupling partners via oxidation state manipulation and arylative coupling in one single catalytic cycle. This reaction features a direct and flexible approach for the preparation of stereodefined arylated allylic alcohols with broad substrate scope under mild conditions. The utility of this protocol is demonstrated through the synthesis of diverse biologically active molecular derivatives.