Upon heating ketenimines of type (III) and carbodiimines derived from isocyanates (VIII) undergo unexpected transformation into benzisothiazolones via 1,5-hydride shift, 1,5-electrocyclization, and [3 + 2] cycloreversion.doi:10.1002/chin.201039132...
ChemInform Abstract: STEROIDS AND SEX HORMONES. PART 264. LEWIS ACID CATALYZED REVERSIBLE (1,5)-HYDRIDE SHIFT IN 3,19-EPOXYSTEROIDSsteroidsDiels-Alder addition of methyl acrylate to 3β-acetoxy-20-keto-5,14,16-pregnatriene (I) afforded an adduct, IIa, which has been transformed into 14α,...
Hybrid quantum mechanical and molecular mechanical (QM/MM) methods are used to estimate the kinetic isotope effects (KIEs) for the 1,2hydride shift reactio... RM Nicoll,SA Hindle,G Mackenzie,... - 《Theoretical Chemistry Accounts》 被引量: 104发表: 2001年 Combined molecular mechanical and qua...
有机反应机理 3 根据Hammond假设，确定活性中间体的结构有助于了解过渡态的结构 因此，活性中间体的研究对有机反应机理的研究具有重要意义 有机反应机理 4 活性中间体包括 自由基卡宾（碳烯）正碳离子负碳离子 乃春（氮烯）苯炔 有机反应机理 5 7.2碳正离子 碳正离子是指碳原子上带正电荷的一类常见有机活性...
They act by deprotonating the rhodium dihydride, allowing nucleophilic attack (see Section 1.26.1.3.5). Sign in to download full-size image Scheme 29. DFT calculations have been carried out for the oxidative addition of a C–H or C–F bond in 1,4-difluorobenzene at [Rh(η5-C5H5)(...
other (Int5) proceeds via an overall 1,4-hydride shift, and disassociation of the diene-ligand inInt3from the metal seems not possible as confirmed by the deuterium labeling and cross-over studies. Finally, transmetallation ofInt5with ArB(OH)2producesInt6, which on subsequent reductive ...
C–H bond functionalization through intramolecular hydride transfer. Angew. Chem. Int. Ed. 53, 5010–5036 (2014). CAS Google Scholar Wang, L. & Xiao, J. Hydrogen-atom transfer reactions. Top. Curr. Chem. 374, 17 (2016). Google Scholar Kumar, P., Thakur, A., Hong, X., Houk, ...
Mechanism for aldose-ketose interconversion by D-xylose isomerase involving ring opening followed by a 1,2-hydride shift. The active site and mechanism of d-xylose isomerase have been probed by determination of the crystal structures of the enzyme bound to various substrates, ... CA Collyer,K ...
If the adjacent substituent is a trichloroacetyl amino group, 1,5-CH insertion competes with the 1,2-hydride shift, and no 1,3-CH insertion can be observed. Both electronic and steric factors are responsible for the switching of the RhII-carbene reaction pathway. The highly stereoselective 1...
112 This rDA method is useful because it can be applied to compounds having groups that are sensitive to lithium aluminum hydride, which had been previously used for regenerating the protected steroidal ring-b diene system. The rDA reaction of the neolignan asatone (124) produces dienon...