المؤلفون: Weiwei Lu, Xin Wen, Xiaojie Lu, Jiaxiang Liu, Zhiqiang Duan

المصدر: Organic Letters. 22:5721-5725

مصطلحات موضوعية: Molecular Structure, Nitromethane, 010405 organic chemistry, Tetrahydroisoquinoline, Organic Chemistry, DNA, 010402 general chemistry, 01 natural sciences, Biochemistry, Combinatorial chemistry, Catalysis, Coupling reaction, Chemical space, 0104 chemical sciences, chemistry.chemical_compound, chemistry, Nucleophile, Alkynes, Tetrahydroisoquinolines, Molecule, Physical and Theoretical Chemistry, Gene Library

الوصف: To expand the chemical space of DNA-encoded library (DEL) technology, we have developed the DNA-compatible cross-dehydrogenative coupling reaction between tetrahydroisoquinolines (THIQs) and a series of nucleophiles such as nitromethane, terminal alkynes, and so on. Both photo- and metal-promoted conditions have been successfully established for this C-1 derivation of THIQs, as exemplified by the addition of nitromethane. All of these new DNA-compatible transformations have paved the way for the divergent oriented synthesis of THIQ-focused DELs.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::cd424a18229fa7ad21512fedc8f4318aTest
https://doi.org/10.1021/acs.orglett.0c01565Test

المؤلفون: Yong Wang, Xin Cui, Xin Wen, X. Peter Zhang

المصدر: Journal of the American Chemical Society. 140:4792-4796

مصطلحات موضوعية: Pyrrolidines, Alkylation, Free Radicals, 010402 general chemistry, Ring (chemistry), 01 natural sciences, Biochemistry, Radical cyclization, Article, Catalysis, chemistry.chemical_compound, Colloid and Surface Chemistry, Organometallic Compounds, Molecule, Molecular Structure, 010405 organic chemistry, Enantioselective synthesis, Stereoisomerism, Cobalt, General Chemistry, Bond formation, Combinatorial chemistry, 0104 chemical sciences, chemistry, Cyclization, Diazo

الوصف: Radical cyclization represents a powerful strategy for construction of ring structures. Traditional radical cyclization, which is based on radical addition as the key step, necessitates the use of unsaturated substrates. Guided by the concept of metalloradical catalysis, a different mode of radical cyclization that can employ saturated C—H substrates is demonstrated through the development of a Co(II)-based system for catalytic activation of aliphatic diazo compounds for enantioselective radical alkylation of various C(sp(3))—H bonds. It allows for efficient construction of chiral pyrrolidines and other valuable 5-membered cyclic compounds. This alternative strategy of radical cyclization provides a new retrosynthetic paradigm to prepare five-membered cyclic molecules from readily available open-chain aldehydes through the union of C—H and C═O elements for C—C bond formation.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::4058be4b26a4bcce311298c2a5ded668Test
https://doi.org/10.1021/jacs.8b01662Test

المؤلفون: X. Peter Zhang, Lukasz Wojtas, Xin Wen, Yong Wang, Xin Cui

المصدر: Journal of the American Chemical Society. 139(3)

مصطلحات موضوعية: Cyclopropanes, Cyclopropanation, chemistry.chemical_element, Alkenes, 010402 general chemistry, 01 natural sciences, Biochemistry, Catalysis, Article, chemistry.chemical_compound, Colloid and Surface Chemistry, Coordination Complexes, Organic chemistry, Sulfonyl, chemistry.chemical_classification, Olefin fiber, Molecular Structure, 010405 organic chemistry, Chemistry, General Chemistry, Cobalt, Porphyrin, Combinatorial chemistry, 0104 chemical sciences, Reagent, Diazo, Azo Compounds

الوصف: Donor-substituted diazo reagents, generated in situ from sulfonyl hydrazones in the presence of base, can serve as suitable radical precursors for Co(II)-based metalloradical catalysis (MRC). The cobalt(II) complex of D2-symmetric chiral porphyrin [Co(3,5-DitBu-Xu(2’-Naph)Phyrin)] is an efficient metalloradical catalyst that is capable of activating different N-arylsulfonyl hydrazones for asymmetric radical cyclopropanation of a broad range of alkenes, affording the corresponding cyclopropanes in high yields with effective control of both diastereoselectivity and enantioselectivity. This Co(II)-based metalloradical system represents the first catalytic protocol that can effectively utilize donor-type diazo reagents for asymmetric olefin cyclopropanation.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::11a9359948533f0c551221049837bca3Test
https://pubmed.ncbi.nlm.nih.gov/28051870Test