Palladium-catalysed carboxytelomerisation of β-myrcene to highly branched C₂₁-esters

Abstract

The first example of the highly-efficient palladium-catalysed carboxytelomerisation of β-myrcene to branched C21-esters is presented.

The Telomerization of 1,3‐Dienes – A Reaction Grows Up

“…This is valid for carboxytelomerization as well. The use of the terpene β‐myrcene leads to the formation of C 21 ‐esters, which are polyunsaturated and highly branched . The “Tolman angle” or cone angle of the ligand plays a major role in this conversion, enabling the solvent‐free conversion of β‐myrcene with methanol to quantitative yields using a catalyst consisting of Pd(OAc) 2 and PCy 2 Ph with a comparably low carbon monoxide pressure of only 3 bar.…”

The Palladium‐Catalyzed Carboxytelomerization of Butadiene with Agrobased Alcohols and Polyols

“…Interestingly,t he carbonylative coupling reaction of 2equivalents of 1,3-butadiene followed by the nucleophilic attack of an alcohol yields alkyl nona-3,8-dienoates (Scheme 1). After early works reported by Tsuji, Billups, and Knifton, [9] it did not attract significant attention in the literature.T he reactionw as only recently used for the synthesis of C21 monoesters from bmyrcene under neutralc onditions [10] and in an intermediate step for the synthesis of diesters from butadiene with pyridine as solvent. All of these are already produced on large scale from agro-resources, furthers trengthening the attractivenesso fs uch transformation in the context of efficient biomass upgrading.…”

Homogeneously Catalyzed 1,3‐Diene Functionalization – A Success Story from Laboratory to Miniplant Scale

“…Very recently, we have shown that the carboxytelomerization of β ‐myrcene with alcohols is viable to synthesize highly branched C21‐esters with potential industrial applications. Using palladium acetate and dicyclohexyl phenyl phosphine as optimal catalyst in neat β ‐myrcene without any additional solvent and under benign carbon monoxide pressures of 3 bar, yields and selectivities of the desired esters of up to 99 % can be achieved …”

“…Using palla-dium acetate and dicyclohexyl phenyl phosphine as optimal catalyst in neat b-myrcene without any additional solvent and under benign carbon monoxide pressures of 3 bar, yields and selectivities of the desired esters of up to 99 % can be achieved. [99]…”