A Pd(0)-catalyzed intramolecular aryldifluoromethylation of activated alkenes under mild reaction conditions has been developed. This reaction provides a new method for construction of a variety of difluoromethylated oxindoles. Mechanistic investigations indicate that a difluoromethyl radical, which was triggered by Pd(0), initiated the cascade sequence through an addition to the alkene.

A highly efficient intermolecular cascade dearomatization of substituted indoles with benzodithiolylium tetrafluoroborate has been developed. This reaction provides a novel strategy to synthesise C3 methyl-substituted pyrroloindolines and furoindolines under mild reaction conditions, the utility of which has been demonstrated by the synthesis of esermethol and physovenine in a highly concise ma...

An efficient and expeditious DABCO-mediated synthesis of functionalized enamides from alkenes is delineated. The reaction proceeds through an unprecedented cascade involving an Aza-Michael addition/α-bromination/elimination and a Morita-Baylis-Hillman type reaction to generate functionalized enamides in a regio- & stereoselective fashion.

A novel and efficient cascade annulation of tertiary α-hydroxy ketones and dimethyl but-2-ynedioate is reported. The reaction, which only requires a base as the promoter, provides a straightforward access to polysubstituted pyrano[4,3-a]quinolizine-1,4,6(2H)-triones and 2H-pyran-2,5(6H)-diones under very mild reaction conditions.

An unexpected Sc(OTf)3-catalyzed and air-mediated cascade reaction of o-aminoacetophenones with methanamines was discovered as an efficient synthetic approach to a novel class of fluorescent fused-four-ring dibenzo[b,h][1,6]naphthyridine derivatives. Two possible mechanisms of the reaction were proposed. The photophysical properties of the dibenzo[b,h][1,6]naphthyridine were initially considered.

Irradiation of terminal aromatic γ,δ-epoxy ketones with a 450 W UV lamp led to Norrish type II cyclization/semi-pinacol rearrangement cascade reaction which formed the benzocyclobutanones containing a full-carbon quaternary center, whereas irradiation of substituted aromatic γ,δ-epoxy ketones led to the indanones through a photochemical epoxy rearrangement and 1,5-biradicals cyclization tandem ...

A new ring expansion of 2-aminobenzothiazoles with alkynyl carboxylic acids was developed, which allows for one-pot synthesis of 1,4-benzothiazines in moderate to excellent yields. The cascade reaction was achieved through decarboxylative coupling, nucleophilic ring-opening reaction and intramolecular hydroamination process.

A one-pot cascade reaction of 1-arylpenta-3,4-dien-2-ones with activated ketones allowed for an efficient and sustainable synthesis of 2-arylphenols. Moreover, this reaction was also found to be compatible and combinable with Pd-catalyzed C-H activation and carbonylation of the in situ formed 2-aryl phenols, thus resulting in a highly convenient and atom-economic synthesis of dibenzopyranones.

An efficient cascade reaction of 2,3-allenoic acids with dialkyl azodicarboxylate in the presence of PPh3 affording 1,2-bis(alkoxycarbonyl)pyrazol-3-ones in moderate yields has been developed. The reaction may proceed via the intramolecular Michael addition of the expected 2,3-allenoyl hydrazines.

A reactive cyclic iminium induced one-pot Groebke-Blackburn-Bienayme (GBB) double annulation cascade (DAC) for the synthesis of skeletally diverse DHIQ salts has been described. The key features of this protocol are transition-metal and solvent-free, mild reaction conditions, robust method, one-step construction of two privileged heterocyclic rings, clean reaction profile and operational simpli...