Mass Efficiency of Alkene Syntheses with Tri- and Tetrasubstituted Double Bonds

Environmental
factors and process mass intensity were determined and
evaluated for more than 30 standard procedures for the synthesis of
alkenes with tri- and tetrasubstituted double bonds. They contain
some of the most commonly used reaction types for the synthesis of
alkenes, e.g., Peterson, Shapiro, Heck, Suzuki, and Negishi. Four
kinds of syntheses of geminal dihalides were also considered. The
highest efficiency is found when employing the olefin metathesis reaction
followed by other modern catalytic processes, and the lowest efficiency
is found with the Julia–Lythgoe process. Several types of McMurry
coupling reactions show that the efficiency is dependent on the variant
of this type of reaction. These metrics point out weaknesses as well
as optimization potentials and show which performances can be expected.
This could provide an orientation when mass efficiency aspects are
relevant during the synthesis planning of alkenes with tri- and tetrasubstituted
double bonds.