Hypervalent Iodine as a Terminal Oxidant in Wacker-Type Oxidation of Terminal Olefins to Methyl Ketones
作者:Dipali A. Chaudhari、Rodney A. Fernandes
DOI:10.1021/acs.joc.6b00137
日期:2016.3.4
the Wacker process for C═O bond formation in terminal olefins can be initiated by a combination of the Pd(II) and hypervalentiodinereagent, Dess–Martin periodinane to generate methyl ketones. This operationally simple and scalable method offers Markovnikov selectivity, has good functional group compatibility, and is mild and high yielding.
Scandium Triflate Catalyzed Allylation of Acetals and <i>gem</i>-Diacetates: A Facile Synthesis of Homoallyl Ethers and Acetates
作者:Jhillu S. Yadav、Basi V. Subba Reddy、P. Srihari
DOI:10.1055/s-2001-13379
日期:——
Scandium triflate catalyzes efficiently the allylation reactions of acetals and gem-diacetates with allyltrimethylsilane at ambient temperature to afford the corresponding homoallyl ethers and acetates in high yields. Also it is found to be effective for the direct formation of homoallyl ethers from aldehydes and allylsilane in presence of trimethylorthoformate.
Indium(III) Chloride Catalyzed Allylation of<i>gem</i>-Diacetates: A Facile Synthesis of Homoallyl Acetates
作者:J. S. Yadav、B. V. Subba Reddy、Ch. Madhuri、G. Sabitha
DOI:10.1246/cl.2001.18
日期:2001.1
Indium(III) chloride is found to catalyze efficiently the allylation of gem-diacetates with allyltrimethylsilane at room temperature to afford the corresponding homoallylic acetates in high yields with good regioselectivity.
Oxonia-Cope Rearrangement and Side-Chain Exchange in the Prins Cyclization
作者:Stuart R. Crosby、John R. Harding、Clare D. King、Gregory D. Parker、Christine L. Willis
DOI:10.1021/ol0102850
日期:2002.2.1
[GRAPHICS]Evidence is presented here for the mechanism of the Prins cyclization of benzylic homoallylic alcohols, which shows that the outcome of the reaction is dependent upon the substituents on the aromatic ring. The presence of an electron-rich aromatic ring favors an oxonia-Cope rearrangement yielding a symmetrical tetrahydropyran as the major product formed via a side-chain exchange process. In contrast, with electron-deficient aromatic rings the expected 2,4,6-trisubstituted tetrahydropyran is formed.
Prins Cyclizations: Labeling Studies and Application to Natural Product Synthesis
作者:Stuart R. Crosby、John R. Harding、Clare D. King、Gregory D. Parker、Christine L. Willis
DOI:10.1021/ol020127o
日期:2002.10.1
[GRAPHICS]The first syntheses of two natural products, catechols 1 and 2, isolated from Plectranthus sylvestris (labiatae), are reported. Oxygen-18 labeling studies support the proposed intermediacy of a stabilized benzylic cation in the acid-promoted cyclization of an aldehyde and benzylic homoallylic alcohol possessing an electron-rich aromatic ring, In contrast, with an electron-deficient aromatic ring the pathway via a benzylic cation is only minor.