Stereoselective addition reactions with chalcogen electrophiles

Abstract

The addition of chalcogen electrophiles to alkenes is investigated using sulfur and tellurium electrophiles. These reagents have been prepared in analogy to the known and well-investigated selenium counterparts.

Organoselenium Chemistry: Role of Intramolecular Interactions

“…For diselenide 317 , the ability of the oxygen to coordinate to Se was found to be influenced by the size of the substituent R. The larger the substituent, the weaker was the Se···O coordination and inducing effect on the newly formed stereocenter. Therefore, the highest diastereoselectivity on addition to styrene was observed when R = H. More recently, Wirth and co-workers prepared S and Te analogues of compound 317 ; however, their cyclization reaction with unsaturated carboxylic acid gives disappointingly low selectivities …”

Alkene selenenylation: A comprehensive analysis of relative reactivities, stereochemistry and asymmetric induction, and their comparisons with sulfenylation

“…Stereochemical outcomes in the asymmetric reactions of chiral arenesulfenyl chlorides [ 91 ] generally feature both lower diastereoselectivity and chemical yields as compared with analogous asymmetric reactions of areneselenenyl chlorides. Each of these differences is in agreement with the findings discussed in this work, that increasing the degree of substitution at the C=C bond has different effects on k rel values of the two reactions.…”

“…There are far fewer reports of chirality induced by arenesulfenyl chlorides [ 91 ], which are analogous to areneselenenyl compounds 1 [ 32 – 43 ]. Data in Table 7 compare electrophilic cyclizations of alkenes by using compound 1 (X = OTf) [ 32 – 43 91 ] and compound 10 , which is the sulfur analog of the chiral selenium compound 1 (X = Cl) [ 80 ]. Both 1 and 10 react to give products with the same absolute configuration.…”

Synthesis of Selenenium Ions: Isolation of Highly Conjugated, pH-Sensitive 4,4′-Bis(methylimino)-1,1′-binaphthylene-5-diselenenium(II) Triflate

“…Organoselenium compounds, having an intramolecular interaction with a nearby heteroatom(s), have been widely studied as electrophiles in addition reaction with olefins . It involves the formation of a seleniranium ion ( 3 ) as an intermediate, which on reaction with the nucleophile leads to the trans products ( 4 ) (Scheme ) …”