Factors affecting trans/cis olefin ratios in elimination reactions of alkyl bromides

Abstract

Hindrance to free rotation of the alkyl group on C, is used to explain abnormally high translcis olefin ratios and different translcis ratios of the same olefin formed from isomeric substrates in E2 reactions of alkyl bromides.

Photoinduced Palladium-Catalyzed Regio- and Chemoselective Elimination of Primary Alkyl Bromides: A Mild Route to Synthesize Unactivated Terminal Olefins

“…However, such transformations often face challenges because of the harsh reaction conditions involving the use of strong bases and high temperatures, which can lead to limited functional group tolerance and undesired olefin isomerization . Additionally, the thermodynamically more stable internal olefins are often the predominant products over terminal olefins, following Zaitsev’s rule . Despite these drawbacks, dehydrohalogenation reactions are frequently encountered in olefin synthesis, which calls for the development of milder conditions to advance this field.…”