Visible‐Light‐Induced
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‐Selective Migration on Pyridyl Ring: Trifluoromethylative Pyridylation of Unactivated Alkenes
作者:Jinwon Jeon、Yu‐Tao He、Sanghoon Shin、Sungwoo Hong
DOI:10.1002/anie.201912746
日期:2020.1.2
alkenes. The overall process is initiated by the selective addition of a CF3 radical to the alkene to provide a nucleophilicalkyl radical intermediate, which enables an intramolecular endo addition exclusively to the ortho-position of the pyridinium salt. Both secondary and tertiary alkyl radicals are well-suited for addition to the C2-position of pyridinium salts to ultimately provide synthetically
Photo-Induced Cross-Dehydrogenative Alkylation of Heteroarenes with Alkanes under Aerobic Conditions
作者:Jun Xu、Heng Cai、Jiabin Shen、Chao Shen、Jie Wu、Pengfei Zhang、Xiaogang Liu
DOI:10.1021/acs.joc.1c02125
日期:2021.12.17
We report a Minisci-type cross-dehydrogenative alkylation in an aerobic atmosphere using abundant and inexpensive cerium chloride as a photocatalyst and air as an oxidant. This photoreaction exhibits excellent tolerance to functional groups and is suitable for both heteroarene and alkane substrates under mild conditions, generating the corresponding products in moderate-to-good yields. Our method provides
Rule et al., Journal of the Chemical Society, 1931, p. 1478,1481
作者:Rule et al.
DOI:——
日期:——
Picolinyl group as an efficient alcohol protecting group: cleavage with Zn(OAc)2·2H2O under a neutral condition
作者:Ju Yuel Baek、Yong-Joo Shin、Heung Bae Jeon、Kwan Soo Kim
DOI:10.1016/j.tetlet.2005.05.125
日期:2005.8
As an efficient alcohol protecting group, picolinates (Pic), prepared from the corresponding alcohols using commercial picolinoyl chloride, are readily cleaved by Zn(OAc)(2) or Cu(OAc)(2), even in the presence of other common alcohol protecting groups. Moreover, the picolinyl group at C-2 position in carbohydrates can be selectively cleaved to give methyl 4,6-O-benzylidene-3-O-picolinyl-alpha-D-glucopyranoside and 3-O-picolinyl methyl-4,6-O-benzylidene-alpha-D-galactopyranoside in good yields. (c) 2005 Elsevier Ltd. All rights reserved.
Di-p-nitrobenzyl azodicarboxylate (DNAD): an alternative azo-reagent for the Mitsunobu reaction
Di-p-nitrobenzyl azodicarboxylate is prepared in 83.6% yield in two steps as a bright yellow solid, which can be used as an azo-reagent in the Mitsunobureaction. When a chiral secondary alcohol was used, sufficient configurational inversion of alcohol occurred under Mitsunobu conditions. That the hydrazine produced from DNAD is semisoluble in some solvents such as THF and CH2Cl2 makes it separated