Regio- and Stereoselective Ferrier Reaction of O-1,3-Dienyl Acetals Promoted by Organoaluminum Complexes
摘要:
The Ferrier reaction of O-1,3-dienyl acetals promoted by organoaluminum complexes such as methylaluminum bis(2,6-di-tert-butyl-4-methylphenoxide) (MAD) is shown to proceed with a high degree of regio- and stereoselectivity to afford the corresponding alpha-alkenyl-substituted beta-alkoxy aldehydes in good yields. The mechanistic origin of the high regiocontrolling ability of MAD is elucidated. This method, coupled with the easy availability of the requisite substrates, expands the synthetic scope of the Ferrier reaction.
Anhydrous FePO4 as a Cost-Effective and Recyclable Catalyst for Tetrahydropyranylation and Tetrahydrofuranylation of Alcohols and Phenols
作者:Farahnaz K. Behbahani、Mona Farahani
DOI:10.2174/157017811796064485
日期:2011.7.1
In this article, a mild and efficient protocol for the tetrahydropyranylation and tetrahydrofuranylation of various aliphatic and benzylic alcohols and phenols into their corresponding THP and THF ethers (with 3,4-dihydro- 2H-pyran, DHP and 2,3-dihydrofuran, DHF) has been developed using a catalytic amount of anhydrous FePO4 at room temperature and relatively short reaction times in good to excellent yields.
Catalytic vinylogous cross-coupling reactions of rhenium vinylcarbenoids
作者:Ji Chen、Jimmy Wu
DOI:10.1039/c7sc05477g
日期:——
compounds by means of cross-coupling with propargyl ethers as non-obvious allylatingreagents. Data from isotope-labeling and kinetic isotopic studies are consistent with a mechanism that proceeds by vinylidene formation as the rate determining step, followed by 1,5-hydride shift to generate a key rhenium vinylcarbenoid complex. Bond formation occurs at the vinylogous site and the reaction is conveniently
作者:Michael Niestroj、Wilhelm P. Neumann、Terence N. Mitchell
DOI:10.1016/s0022-328x(96)06151-7
日期:1996.7
such as O or N undergo only protodestannylation with this electrophile. The reaction of Z-1,2-bis (trimethylstannyl)-1-alkenes with trimethylsilyl chlorosulphonate followed by hydrolysis with aqueous NaHCO3 provides the corresponding sodium sulphonates. SO2 and SO3 undergo insertion into both tin-carbon bonds in an ipso- and stereospecific manner to form bis-sulphinic- or bis-sulphonic bis(trialkylstannyl)
Z -1,2-双(三甲基锡烷基)-1-烯烃对各种亲电子试剂显示出不同类型的反应行为。对甲苯磺酰基异氰酸酯形成五元含锡氮杂环。1,1-二氯甲基甲基醚与碳官能化的二苯乙烯基烯烃反应生成α,β-不饱和醛,这对于合成其他取代的乙烯基锡烷有用。含有诸如O或N的杂原子的Z -1,2-双(三甲基锡烷基)-1-烯烃与该亲电试剂仅进行原脱锡反应。的反应ž -1,2-双(三甲基锡烷基)-1-烯烃与氯磺酸三甲基甲硅烷随后水解用碳酸氢钠水溶液3提供相应的钠磺酸盐。SO 2SO 3和SO 3以ipso-和立体定向方式插入到锡-碳两个键中,以形成双-磺酸-或双-磺酸的双(三烷基锡烷基)酯。
Efficient tetrahydropyranyl and tetrahydrofuranyl protection/deprotection of alcohols and phenols with Al(OTf)3 as catalyst
作者:D. Bradley G. Williams、Sandile B. Simelane、Michelle Lawton、Henok H. Kinfe
DOI:10.1016/j.tet.2010.04.053
日期:2010.6
A simple and efficient method for the conversion of alcohols and phenols into their corresponding THP and THF ethers at room temperature has been developed using 1 mol % aluminium triflate as catalyst. The deprotectionreaction in the presence of methanol using Al(OTf)3 was equally successful and could be performed at ambient temperature in high yields.
Environmentally Friendly Tetrahydrofuranylation of Alcohols Using NaHSO<sub>4</sub>–SiO<sub>2</sub> under Solvent-free Conditions
作者:Henok H. Kinfe、Sullivan Terblanche、Konanani D. Tshivhase、Livhuwani Ravhura
DOI:10.1246/cl.2012.272
日期:2012.3.5
A simple, environmentally friendly, and efficient tetrahydrofuranylation of alcohols has been developed using NaHSO4–SiO2 (0.5 mol %) as a catalyst under solvent-free conditions to yield corresponding THF ethers in good to excellent yields.