Nickel-catalyzed coupling reactions of alkenes

Abstract

Several reactions of simple, unactivated alkenes with electrophiles under nickel(0) catalysis are discussed. The coupling of olefins with aldehydes and silyl triflates provides allylic or homoallylic alcohol derivatives, depending on the supporting ligands and, to a lesser extent, the substrates employed. Reaction of alkenes with isocyanates yields N-alkyl acrylamides. In these methods, alkenes act as the functional equivalents of alkenyl-and allylmetal reagents.

Recent advances in homogeneous nickel catalysis

“…The reaction is generally accepted to proceed via a concerted oxidative cyclization, followed by either coordination of the reducing agent to Ni or σ-bond metathesis to provide a nickel hydride, and terminated by reductive elimination. Several excellent reviews 3 of the state of the field prior to 2005 exist including couplings of both alkenes 92 and alkynes. 93 …”

Isomerization of allylic alcohols in water catalyzed by transition metal complexes

“…Isomerization mechanisms. 110 The catalytic mechanism for the isomerisation of allylic alcohols 111 in aqueous media was initially investigated by McGrath and 112 Grubbs by using [Ru(H 2 O) 6 ](tos) 2 (tos = p-toluene sulfonate) (1) 113 as catalyst [25]. The most efficient one-step isomerisation process 114 (Scheme 2, path a) requires the double bond migration into an enol 115 (or enolate) intermediate that then rapidly tautomerizes to afford 116 the saturated carbonyl compound [7, [29][30][31][32][33][34].…”

Nickel-Catalyzed Allylic Substitution of Simple Alkenes

“…[8a] Over the past several years, both of our groups have actively investigated other related transformations. [7][8][9] In our ongoing efforts in this area, we have developed highly regioselective nickel-catalyzed threecomponent couplings of alkenes, aldehydes, and silyl triflates, enabling the access to both homoallylic alcohols [8b] and allylic alcohols [8c] by judicious choice of reaction conditions (equation 1). Nickel-catalyzed intermolecular coupling reactions of simple terminal alkenes with α,β-unsaturated carbonyl compounds has also been reported (equation 2).…”