122673-91-0Relevant articles and documents
Palladium-Catalyzed Intermolecular Heck-Type Reaction of Epoxides
Teng, Shenghan,Tessensohn, Malcolm E.,Webster, Richard D.,Zhou, Jianrong Steve
, p. 7439 - 7444 (2018/07/15)
The palladium-catalyzed intermolecular Heck-type reaction of both cyclic and acyclic epoxides is reported with tolerance of typical polar groups and acidic protons. Suitable alkenes include styrenes, conjugate dienes, and some electron-deficient olefins. In reactions of aliphatic terminal epoxides, ring opening occurs selectively at terminal positions, and stereocenters of epoxides are fully retained. Mechanistic studies provide evidence for in situ conversion of epoxides to β-halohydrins, generation of alkyl radicals, and radical addition to alkenes as key steps. Cyclovoltammetric determination of reduction potentials suggests that during activation of alkyl iodides by palladium(0) complexes, inner-sphere halogen abstraction is more likely than outer-sphere single electron transfer.
Regioselective vicinal functionalization of unactivated alkenes with sulfonium iodate(i) reagents under metal-free conditions
Rao, Dodla S.,Reddy, Thurpu R.,Babachary, Kalvacherla,Kashyap, Sudhir
, p. 7529 - 7543 (2016/08/16)
Metal-free, molecular iodine-free direct 1,2-difunctionalization of unactivated alkenes has been reported. The sulfonium iodate(i) reagent efficiently promoted the intermolecular vicinal iodo-functionalization of a diverse range of olefins in a stereo and regioselective manner. This method enables the divergent and straightforward preparation of synthetically useful functionalities; β-iodocarboxylates, β-iodohydrins, and β-iodoethers in a one-step process. Further interconversion of iodo-functionalized derivatives allows easy access to valuable synthetic intermediates en route to biologically active molecules.
Enzymatic preparation of (1S,2R)- and (1R,2S)-stereoisomers of 2-halocycloalkanols
Kolodiazhna, Olga O.,Kolodiazhna, Anastasy O.,Kolodiazhnyi, Oleg I.
, p. 37 - 42 (2013/02/25)
The stereoisomers of cis-2-halocycloalkanols were resolved by a kinetically controlled transesterification with vinyl acetate in the presence of lipases in organic media. High enantioselectivities (ee >98%) and good isolated yields were obtained for all substrates using the appropriate lipase. Burkholderia cepacia lipase was the most efficient enzyme for the resolution of these substrates. The enantiomeric purities of the compounds were defined by derivatization with Mosher's acid and the absolute configurations were determined by chemical correlation.
