Our research group has recently developed a new copper and rhodium catalysed methylenation of carbonyl derivatives using TMSCHN₂, i-PrOH, Ph₃P. We have recently reported two new cascade processes: a formal reductive one-carbon homologation via a rhodium-catalysed methylenation-hydrogenation cascade; and a methylenation-hydroboration cascade process leading to the corresponding organoborane product, wich can be further functionalized. Copper salts which are very efficient to catalyze the methylenation reaction are also known as co-catalyst for cross-coupling reactions; thus one-pot processes that combine olefination and cross-coupling reactions should be particularly efficient. Indeed we wish now to present a new multicatalytic methylenation –hydroboration–Suzuki-coupling one-pot process, which combined rhodium or copper and palladium catalysts. A synthetic strategy towards Abietanes will be also disclosed.