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Formal [4+2] cycloaddition of cyclic enamides with imines derived from aromatic amines gave the 4-arylhexahydropyrroloquinoline skeleton in one step as mixtures of diastereoisomers. Aromatic imines derived from formaldehyde and methylglyoxalate also participated in this chemistry, with the latter favouring formation of the endo -cycloadduct. The cycloadducts derived from methylglyoxalate were unstable and fragmented to give highly substituted quinolines under both neutral and basic conditions. Imines derived from 3-cyanoacrolein also underwent cycloaddition and gave an advanced potential precursor to martinellic acid, albeit with poor diastereoselectivity.

The tricyclic core of martinelline and martinellic acid was rapidly assembled utilising an imino Diels–Alder reaction of an imine derived from cinnamaldehyde with a cyclic enamide. The cycloaddition was completely regioselective though the exo – endo selectivity was poor. These diastereoisomers were readily separated by flash chromatography and the relative stereochemistry of the exo -isomer confirmed by single crystal X-ray crystallography. This intermediate was converted to the central core of the aforementioned alkaloids in five additional synthetic operations.

Terminally N-substituted dienes derived from 3-methylisoindolin-1-one, 4-isopropyl- and 4-phenyloxazolidin-2-one undergo Diels–Alder reaction with a range of activated dienophiles. The reactions reported are completely regio- and endo-selective, with the diastereoisomeric excess with respect to the auxiliary good to excellent in most of the cases reported. A model has been developed for rationalising the stereochemical outcome of these reactions.

Piclavines A1 and A2 have been synthesised for the first time. The route is short with the key step being the reaction of a bicyclic N -acyl iminium ion with 3-trimethysilyl-1-decene. This convergent strategy gave exclusively compounds in which the pendant decenyl group was axial , as a 6:1 mixture of E : Z- alkene diastereoisomers. Reduction of the lactam carbonyl group gave a 6:1 mixture of piclavines A1 and A2.

Reaction of 2′-bromodeoxybenzoins with copper powder in refluxing dimethylacetamide gives the corresponding 2-phenylfuran in good yields.