Highly selective intra- and intermolecular coupling reactions of diazo compounds to form cis-alkenes using a ruthenium porphyrin catalyst.

[Ru(2,6-Cl(2)TPP)(CO)] catalyzed intramolecular coupling reactions of bisdiazoacetates and intermolecular coupling reactions of monodiazoacetates to afford the coupling products in up to 76% and 93% yields, respectively. Only the cis isomers were obtained from the reactions. Employing such a ruthenium-catalyzed coupling reaction of a diazo compound as a key step allowed the synthesis of Patulolide B in 67% yield with a ratio of >40:1 against its trans isomer.