A Mild, Efficient, and Selective Method for the Desilylation of More Common Trialkylsilyl Ethers by Cerium(III) Chloride Heptahydrate and Sodium Iodide in Acetonitrile
Regiochemical control of the ring opening of 1:2-epoxides by means of chelating processes. 10. Synthesis and ring opening reactions of mono- and difunctionalized cis and trans aliphatic oxirane systems
The regiochemical outcome of the ring opening of 1:2-epoxides through chelation processes assisted by metal ions, was verified in mono- and difunctionalized aliphatic oxirane systems bearing the heterofunctionality (OR) in an homoallylic and/or allylic relationship to the oxirane ring. The effect of the distance of the OR functionality from the oxirane ring and of the type of protective group on the
Synthesis of New Nucleoside Analogues Comprising a Geminal Difluorocyclopropane Moiety as Potential Antiviral/Antitumor Agents
作者:Yao-Ling Qiu、Jiri Zemlicka
DOI:10.1080/07328319908044881
日期:1999.10
Geminal difluorocyclopropane analogues of nucleosides 7a - 7e were synthesized. Compounds 7a and 7c - 7e were obtained by alkylation of nucleic acid bases or their appropriate precursors with (cis)-1-benzyloxymethyl-2-bromomethyl-3,3-difluorocyclopropane (8). Analogue 7b was prepared by hydrolysis of 2-amino-6-chloropurine derivative 7e. Compounds 7a - 7d did not exhibit any antiviral activity against HCMV, HSV-1, HSV-2 EBV, VZV, HBV and HIV-1 or antitumor effects against murine leukemia L1210, mouse tumors PO3 or C38 and human tumor H15.
Preparation of methylene-gem-difluorocyclopropanes and its reactivity as Michael acceptor
Preparation of methylene-gem-difluorocyclopropanes 3 was achieved through the selenoxide elimination reaction derived from gem-difluorocyclopropylmethanols 1, while this method can not be applied to non-fluorinated cyclopropylmethanols. The methylene-gem-difluorocyclopropane 3 showed a high reactivity as a Michael acceptor in the reaction with thiol or amine. (C) 1997 Elsevier Science Ltd.
Efficient and Stereoselective Synthesis of Allylic Ethers and Alcohols
作者:Jiří Pospíšil、István E. Markó
DOI:10.1021/ol062433y
日期:2006.12.1
[Structure: see text] A short and efficient synthesis of allylic TBS ethers and allylic alcohols has been developed, based upon a unique Kocienski-Julia olefination reaction. Allylic alcohols and allylicethers are obtained in good to excellent yields and with high (E)-selectivity. The conditions are mild and the procedure is broadly applicable.
A Mild, Efficient, and Selective Method for the Desilylation of More Common Trialkylsilyl Ethers by Cerium(III) Chloride Heptahydrate and Sodium Iodide in Acetonitrile
Treatment of trialkylsilyl ethers with cerium(III) chloride heptahydrate and sodium iodide in acetonitrile provides a simple, convenient, and chemoselective process for desilylation, and the parent alcohol was obtained in high yield. The trialkylsilyl ethers have been cleaved selectively in the presence of acetate, benzyl and tetrahydropyranyl ethers.