Transition‐Metal‐Catalyzed Laboratory‐Scale Carbon–Carbon Bond‐Forming Reactions of Ethylene

Abstract

Ethylene, the simplest alkene, is the most abundantly synthesized organic molecule by volume. It is readily incorporated into transitionmetal–catalyzed carbon-carbon bond-forming reactions through migratory insertions into alkylmetal intermediates. Because of its D2h symmetry, only one insertion outcome is possible. This limits byproduct formation and greatly simplifies analysis. As described within this Minireview, many carbon–carbon bond-forming reactions incorporate a molecule (or more) of ethylene at ambient pressure and temperature. In many cases, a useful substituted alkene is incorporated into the product.

Migratory Arylboration of Unactivated Alkenes Enabled by Nickel Catalysis

“…[1] Tr ansition-metal catalysis enables alkene difunctionalization that proceeds in ah ighly selective and efficient manner. [1] Tr ansition-metal catalysis enables alkene difunctionalization that proceeds in ah ighly selective and efficient manner.…”

Theoretical investigation on the mechanism of FeCl3-catalysed cross-coupling reaction of alcohols with alkenes

“…The following findings can be revealed by our calculations. (1) The entire catalytic cycle contains three successive stages: hydrogen abstraction from C 1 of phenylpropanol via TS (1)(2) ; free-radical addition to form the new C(sp 3 )-C(sp 3 ) bond via TS (3)(4) ; and migration of H atom of metal hydride (H-FeCl 3 ) via TS (4)(5) , leading to the formation of coupling product P. (2) The energy profile of the whole catalytic cycle shows that the hydrogen abstraction is the rate-determining step. The activation barriers for the hydrogen abstraction are computed to be 19.7 and 34.2 kcal/mol on the quartet and sextet PES, respectively.…”

“…This process passes through the second transition state TS (3)(4) to form the intermediate IM4. In TS (3)(4) , the C 1 -C 2 distance of 2.23 Å is shorter than the value of 2.93 Å in IM3. The C 1 atom is much closer to the C 2 atom, so that the free-radical addition can occur easily.…”

“…The C 1 atom is much closer to the C 2 atom, so that the free-radical addition can occur easily. The barrier height for free-radical addition via TS (3)(4) is computed to be 5.5 kcal/mol in the quartet state. From the intermediate IM3 to intermediate IM4, the bond length of C 2 -C 3 is slightly elongated from 1.35 to 1.46 Å .…”

“…C-C bond formation is a vital procedure to construct complex molecules from simple substrates in organic synthesis [1][2][3]8]. Recently, there have been some efforts to develop C-C bond-forming reactions based on C-H bond activation.…”