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A new palladium–indium diastereoselective cascade allylation of imines using allenes and aryl iodides is described; N-tosyl and N-aryl homoallyl amines were obtained in moderate to good yields and excellent diastereoselectivity was observed when enantiomerically pure N-tert-butanesulfinyl imines were employed in the cascade.

The diastereoselective synthesis of azabicyclo[3.1.0]hexanes bearing different substituents on all positions of the cyclopropane ring has been achieved in moderate to good yields.

The tandem 1,3-azaprotiocyclotransfer–cycloaddition reaction between aldoximes and divinyl ketone affords mixtures of exo- and endo-isomers of substituted 1-aza-8-oxabicyclo[3.2.1]octan-4-ones, the ratio of which is dependent on the E/Z geometry of the starting oxime and its ability to isomerise under the thermal reaction conditions.

2-Haloaryl aldehydes and ketones react with allene (1 atm) in the presence of 2 mol% of a non-phosphine cyclopalladated catalyst to afford cyclopentenols and cyclohexenols via nucleophilic cyclisation of intermediate π-allylpalladium species. A possible mechanism for this unusual reactivity is suggested.

Cyclisation of chloroformates onto proximate alkyne functionality in the presence of a Pd(0) catalyst followed by anion capture affords α-methylene-γ-butyrolactone derivatives in moderate to good yields.

Substituted pyrroles are formed in moderate to good yields by the Pd-catalysed cyclisation of enamines containing β-vinyl bromide functionalities.

Cyclopalladated phosphine free pyrazole complexes 1 and benzothiazole complexes 2 are excellent catalysts for the Heck vinylation of aryl iodides and termolecular queuing cascades, leading to turnover numbers of >106 in some cases, at moderate temperatures; these catalysts show high thermal stability and are not sensitive to moisture and air.

Chemo- and regio-specific palladium catalysed four component processes, involving formation of 3 new bonds, initiated by oxidative addition of Pd(0) with aryl iodides followed by sequential incorporation of CO (1 atm), a polymer supported allene and an amine provides complex heterocycles with 3 points of diversity in good yield and excellent purity after cleavage.

Pd(0) catalysed termolecular queuing processes involving cyclisation of aryl halides onto proximate alkynes, allene (1 bar) insertion, transmetallation of the resulting π-allylpalladium(II) species with indium and addition to an aldehyde affords heterocyclic and carbocyclic dienes.

The tandem 1,3-azaprotiocyclotransfer–cycloaddition reaction between aldoximes and divinyl ketone affords the exo- isomers of substituted 1-aza-8-oxabicyclo[3.2.1]octan-4-ones when a substoichiometric amount of hafnium(IV) chloride is added.

The synthesis of 3,3-disubstituted and 3-methyleneoxindoles by palladium(0) catalysed cyclisation of carbamoyl chlorides onto proximate alkene or alkyne groups has been achieved in good yields.

A novel short synthetic route to annelated benzazepines, using additive enhanced palladium-indium catalytic 3-component cascade methodology is described.

Palladium catalysed [2 + 2 + 1] cycloaddition of 1,6-heptadiynes with CO (1 atm) furnishes bicyclo[3.3.0]octa-1,5-dien-3-ones in 30-74% yield.