C–N Bond Formation from Allylic Alcohols via Cooperative Nickel and Titanium Catalysis

Abstract

Amination of allylic alcohols is facilitated via cooperative catalysis. Catalytic Ti(O- i-Pr) is shown to dramatically increase the rate of nickel-catalyzed allylic amination, and mechanistic experiments confirm activation of the allylic alcohol by titanium. Aminations of primary and secondary allylic alcohols are demonstrated with a variety of amine nucleophiles. Diene-containing substrates also cyclize onto the nickel allyl intermediate prior to amination, generating carbocyclic amine products. This tandem process is only achieved under our cooperative catalytic system.

Nickel‐Catalyzed Allylic Substitution Reactions: An Evolving Alternative

“…Michaelis found that by replacing n-Bu 4 NOAc with Ti(O-iPr) 4 , the reaction proceeded much faster and could be conducted under ambient temperature. [65] This additive was found to activate the allyl alcohol towards oxidative addition presumably by the formation of a Ti(O-allyl) n (O-iPr) m species. Under these conditions, it was possible to develop a tandem cyclization/amination of diene-containing substrates (Scheme 25).…”

Cobalt-Catalyzed Allylation of Amides with Styrenes Using DMSO as Both the Solvent and the α-Methylene Source

“…However, a highly active and synthetic dioxazolone species was still involved as the amidating reagent. In addition, to the best of our knowledge, there have been few reports that have shown direct synthesis of more common allylic amines, especially for those for which no substituent was installed at the α-position . In this context, exploring a new strategy for the efficient construction of common allylic amines from the readily accessible starting materials is still not only highly desirable but also of great significance.…”

Boron-Templated Dimerization of Allylic Alcohols To Form Protected 1,3-Diols via Acid Catalysis

“…Our research group is interested in the use of simple allylic alcohol substrates as coupling partners for transition-metal-catalyzed reactions. , Recently, while investigating the use of nickel catalysts for Suzuki reactions with unprotected allylic alcohol electrophiles, we discovered that copper­(II) triflate catalyzed a unique dimerization of allylic alcohols to form new C–C and C–O bonds (red) across one of the alkenes (Figure b). In this unprecedented transformation, the boronic acid is incorporated into the structure of the product ( 2 ), but can be easily removed under basic conditions to reveal a new 1,3-diol structure ( 3 ).…”