Nucleophilic displacement of homoallylic tosylates: influence of steric hindrance and conformational rigidity

Easy and direct conversion of tosylates and mesylates into nitroalkanes

“…In fact, with the exception of a couple of examples reporting the conversion of 1-BuOTs [26] and homoallylic tosylates [34] into the corresponding nitro compounds, to the best of our knowledge, no general methods are available in literature.…”

Photoredox‐Catalyzed Cyclopropanation of 1,1‐Disubstituted Alkenes via Radical‐Polar Crossover Process

“…In contrast to the superior reactivity of tosylate over halides in typical bimolecular nucleophilic substitution, the bulky tosylate displayed inferior reactivity compared to the much smaller chloride, yielding 3 g (38%) and 15 (45%). The steric hindrance and conformational rigidity could possibly account for the reverse trend of the above leaving group ability . Expectedly, the faster reaction was with bromide as leaving group compared to tosylate in the case of the reaction of bromomethyl radical with 14 , giving the cyclopropanes 11 and 15 in a ratio of 1:3.3 with a total yield of 78%.…”

“…The steric hindrance and conformational rigidity could possibly account for the reverse trend of the above leaving group ability. [21] Expectedly, the faster reaction was with bromide as leaving group compared to tosylate in the case of the reaction of bromomethyl radical with 14, giving the cyclopropanes 11 and 15 in a ratio of 1:3.3 with a total yield of 78%. Of note, the ratio of tosylate and halo-containing cyclopropane was decreased with the reaction time extending, suggesting the contamination reaction of the substitution of tosylate with halide ion under this visible-lightmediated reaction conditions.…”