Acyclic nucleoside phosphonates have been prepared in a straightforward manner and in high yields by an enantioselective palladium-catalyzed allylic substitution involving nucleic bases as nucleophiles followed by cross-metathesis reaction with diethyl allylphosphonate.

Branched allyl amines or linear amines can be obtained from E-4-hydroxybuten-2-yl methyl carbonate using the palladium/1,2-diaminocyclohexane (DACH)-catalysed allylic amination by just starting from the unprotected or the protected derivative, respectively. Unhindered primary amines can be used as nucleophiles, thus enlarging the scope of the Pd/ DACH catalytic system. Hydrogen bonding involving the free hydroxy group in the unprotected allylic carbonate is proposed to be responsible for the control of the regioselectivity to afford branched isomers, obtained in high ee. A short and enantioselective formal synthesis of the glycosidase inhibitor fagomine is described using this method.

A formal enantioselective synthesis of nectrisine, a potent α-glucosidase inhibitor, was carried out starting from butadiene monoepoxide through a synthetic sequence involving enantioselective allylic substitution, cross-metathesis, dihydroxylation, and cyclization.

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