N1‐Bromoimides 1 add to alkenes 3 in a free‐radical chain reaction on a multigram scale with imidyl radicals 2 as chain carriers. High regioselectivities are found when the substituents at the non‐attacked sp2 carbon atom to the alkene 3 are alkoxy or sterically bulky residues. The stereochemistry of the addition is determined by the bromine transfer from the N1‐bromoimide 1 to the adduct radical 4. Formation of the trans1‐addition products 5 is favored. In competition reactions vinyl ethers react faster with the imidyl radicals 2 than alkyl‐substituted alkenes.
The addition of N‐chlorophthalimide (1b) to alkenes 3 via phthalimidyl radicals introduces a chlorine atom and an imidyl moiety to vicinal C‐atoms of a carbon chain. The yields depend on the substituents of the alkene 3. The regioselectivity can be explained by steric and electronic effects; differences in the behavior of the addition of N‐chlorophthalimide (1b) and N‐bromophthalimide (1a) can be explained by a reversible attack of the phthalimidyl radical to the double bond.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.