- Crystal structure, thermal decomposition mechanism and catalytic performance of hexaaquaaluminum methanesulfonate
-
Hexaaquaaluminum methanesulfonate crystals, [Al(H2O)6][CH3SO3]3 were synthesized by a hydrothermal reaction of Al(OH)3 with methanesulfonic acid. Single-crystal diffraction determination revealed that Al3+ was coordinated by six water molecules in octahedral geometry, while the CH3SO3 – anion connected with Al3+ through coordinated water molecules by hydrogen bonds. The six-coordinate environment of Al was also determined by 27Al MAS NMR measurement. Thermogravimetric analysis and Fourier transform infrared spectroscopy showed that the decomposition intermediate at 265–365?°C was Al2(μ-OH)(CH3SO3)5 and the final product was amorphous Al2O3 residue with about 0.8 wt% SO3 at 520–800?°C. A pure phase of [Al(H2O)6][CH3SO3]3 was confirmed by powder X-ray diffraction analysis. Esterification of n-butyric acid with n-butanol and ketalization of cyclohexanone with glycol catalyzed by [Al(H2O)6][CH3SO3]3 and Al2(μ-OH)(CH3SO3)5, respectively, proceeded in 100% yield by continuously removing the produced water. In the case of tetrahydropyranylation of n-butanol at room temperature in dichloromethane, the catalytic activity of [Al(H2O)6][CH3SO3]3 was much lower than that of Al2(μ-OH)(CH3SO3)5. Furthermore, both [Al(H2O)6][CH3SO3]3 precursor and Al2(μ-OH)(CH3SO3)5 catalysts could be recycled.
- Wang, Rui,Li, Rongrong,Jiang, Heng,Gong, Hong,Bi, Yanfeng
-
p. 1327 - 1338
(2017/04/06)
-
- Synthesis of Ethers via Reaction of Carbanions and Monoperoxyacetals
-
Although transfer of electrophilic alkoxyl ("RO+") from organic peroxides to organometallics offers a complement to traditional methods for etherification, application has been limited by constraints associated with peroxide reactivity and stability. We now demonstrate that readily prepared tetrahydropyranyl monoperoxyacetals react with sp3 and sp2 organolithium and organomagnesium reagents to furnish moderate to high yields of ethers. The method is successfully applied to the synthesis of alkyl, alkenyl, aryl, heteroaryl, and cyclopropyl ethers, mixed O,O-acetals, and S,S,O-orthoesters. In contrast to reactions of dialkyl and alkyl/silyl peroxides, the displacements of monoperoxyacetals provide no evidence for alkoxy radical intermediates. At the same time, the high yields observed for transfer of primary, secondary, or tertiary alkoxides, the latter involving attack on neopentyl oxygen, are inconsistent with an SN2 mechanism. Theoretical studies suggest a mechanism involving Lewis acid promoted insertion of organometallics into the O-O bond.
- Kyasa, ShivaKumar,Meier, Rebecca N.,Pardini, Ruth A.,Truttmann, Tristan K.,Kuwata, Keith T.,Dussault, Patrick H.
-
p. 12100 - 12114
(2016/01/09)
-
- 3,5-Dinitrobenzoic acid catalyzed synthesis of 2,3-unsaturated O- and S-glycosides and tetrahydropyranylation of alcohols and phenols
-
A simple procedure for the synthesis of 2,3-unsaturated glycosides in acetonitrile and tetrahydropyranylation of alcohols and phenols in dichloromethane in the presence of 3,5-dinitrobenzoic acid is described. A variety of alcohols and thiols are reacted with glycals to give the desired products in high yields with high α-selectivity.
- Bodipati, Naganjaneyulu,Palla, Srinivasa Rao,Komera, Venkateshwarlu,Peddinti, Rama Krishna
-
supporting information
p. 6878 - 6881
(2015/02/02)
-
- Tetrahydropyranylation of alcohols and phenols using polystyrene supported lewis acids as catalysts
-
Polystyrene supported TiCl4 (Ps-TiCl4) and polystyrene supported FeCl3(Ps-FeCl3) were prepared by coordinating Lewis acids with polystyrene. The catalysts were characterized by TGA, BET, SEM, IR and pyridine-adsorbed IR. The loading of Ps-TiCl4 and Ps-FeCl3 were 0.35 and 0.3 mmol·g-1 respectively. Both catalysts were found to be efficient for the tetrahydropyranylation and detetrahydropyranylation of various alcohols and phenols in different solvents. Two catalysts can be recovered and reused for five times with good activity. Polystyrene supported TiCl4 (Ps-TiCl4) and polystyrene supported FeCl3(Ps-FeCl 3) were prepared by coordinating Lewis acids with polystyrene. The catalysts were characterized by TGA, BET, SEM, IR and pyridine-adsorbed IR. The loading of Ps-TiCl4 and Ps-FeCl3 were 0.35 and 0.3 mmol·g-1 respectively. Both catalysts were found to be efficient for the tetrahydropyranylation and detetrahydropyranylation of various alcohols and phenols in different solvents. Two catalysts can be recovered and reused for five times with good activity. Copyright
- Zhang, Yi,Dou, Qianqian,Liu, Yuan,Dai, Liyan,Wang, Xiaozhong,Chen, Yingqi
-
p. 2567 - 2572
(2013/01/15)
-
- Solvent-free tetrahydropyranylation of alcohols catalyzed by amine methanesulfonates
-
A comparative study of tetrahydropyranylation of alcohols under various solvents or solvent-free conditions using different amine methanesulfonates as catalysts shows that tetrahydropyranyl ethers of alcohols are obtained under solvent-free conditions in good yields using catalytic amounts of triethylenediamine methanesulfonate, 1,6-hexanediamine methanesulfonate, diethylenetriamine methanesulfonate and pyridine methanesulfonate, respectively. The reaction occurs readily in short times at room temperature catalyzed by these catalysts, especially triethylenediamine methanesulfonate. Some of the major advantages of this procedure are that the catalysts are environmentally friendly, highly effective, and easy to prepare and handle. The reaction is also clean and needs no solvent, and the work-up is very simple.
- Wang, Rui,Sun, Mingzhu,Jiang, Heng
-
experimental part
p. 61 - 67
(2012/02/16)
-
- Metal benzenesulfonates/acetic acid mixtures as novel catalytic systems: Application to the protection of a hydroxyl group
-
A surprising synergistic effect has been discovered in mixtures of metal benzenesulfonates (Co, Al, Ni, Zn, Cd, Pr, La, Cu, Mn) and acetic acid, leading to active catalytic systems for the tetrahydropyranylation of alcohols and phenols to produce tetrahydropyranyl ethers. All reactions proceed mildly and efficiently with moderate to high yields at room temperature without solvent. After the reaction, the metal benzenesulfonate can be easily recovered and reused many times. The efficiency of these systems might result from the "double activation" by Bronsted and Lewis acid catalysis.
- Wang, Min,Gao, Jingjing,Song, Zhiguo
-
experimental part
p. 1349 - 1352
(2011/01/11)
-
- 1,6-Hexanediamine methanesulfonate: A mild and efficient catalyst for the tetrahydropyranylation of alcohols under solvent-free conditions
-
Various alcohols react with 3,4-dihydro-2 H-pyran under mild conditions using a catalytic amount of 1,6-hexanediamine methanesulfonate. It affords the corresponding tetrahydropyranyl ethers in good yields at a faster rate in the absence of solvent. Taylor & Francis Group, LLC.
- Wang, Rui,Jiang, Heng
-
experimental part
p. 171 - 176
(2012/01/05)
-
- Copper nitrate/acetic acid as an efficient synergistic catalytic system for the chemoselective tetrahydropyranylation of alcohols and phenols
-
Tetrahydropyranylation of alcohols and phenols was accomplished successfully using copper nitrate and acetic acid as a synergistic catalyst at room temperature under solvent-free condition. Compared with other synergistic catalytic systems, copper nitrate/acetic acid proved to be the most efficient. Both alcohols (primary, secondary, tertiary, benzylic, cyclic, allyl, cinnamyl, and furyl) and phenols reacted smoothly in high yields. Graphical abstract: [Figure not available: see fulltext.]
- Wang, Min,Song, Zhi-Guo,Gong, Hong,Jiang, Heng
-
experimental part
p. 177 - 179
(2010/04/02)
-
- Dowex 50WX4-100: An efficient catalyst for the tetrahydropyranylation of alcohols
-
The ion-exchange resin Dowex 50WX4-100 has been found to catalyze efficiently the protection reaction of a variety of alcohols with 2,3-dihydro-4H pyran (DHP) and dichloromethane at ambient conditions. Copyright Taylor & Francis Group, LLC.
- Poon,Banerjee, Ajoy K.,Bedoya, Liadis,Laya, Manuel S.,Cabrera, Elvia V.,Albornoz, Karla M.
-
experimental part
p. 3369 - 3377
(2011/03/19)
-
- AI(OTf)3 - A highly efficient catalyst for the tetrahydropyranylation of alcohols under solvent-free conditions
-
A simple and highly efficient method has been developed for the tetrahydropyranylation of alcohols by their reaction with 3,4-dihydro-2H-pyran (DHP) using a catalytic amount (0.01-1 mol%) of aluminium triflate under solvent-free conditions. The effect of various factors like temperature, amount of the catalyst, and molar ratio of substrates on the reaction conditions has also been studied. The comparative study of tetrahydropyranylation of benzyl alcohol using various catalysts including some reported ones shows the efficiency of this catalyst.
- Kamal, Ahmed,Naseer A Khan,Srikanth,Srinivasa Reddy
-
scheme or table
p. 1099 - 1104
(2009/03/11)
-
- Copper p-toluenesulfonate/acetic acid: A recyclable synergistic catalytic system for the tetrahydropyranylation of alcohols and phenols
-
Copper p-toluenesulfonate/acetic acid was found to be an efficient, chemoselective synergistic catalytic system, with catalyst loading as low as 0.3 mol% leading to clean, high-yielding tetrahydropyranylation of a variety of alcohols and phenols. By simple phase-separation, copper p-toluenesulfonate can be easily recovered and reused for several times without deterioration in catalytic activity.
- Wang, Min,Song, Zhi-Guo,Jiang, Heng,Gong, Hong
-
experimental part
p. 601 - 604
(2009/08/07)
-
- Generally applicable organocatalytic tetrahydropyranylation of hydroxy functionalities with very low catalyst loading
-
This paper presents the first acid-free, organocatalytic tetrahydropyran and 2-methoxypropene protection of alcohols, phenols, and other ROH derivatives utilizing privileged N,N′-bis[3,5-bis(trifluoromethyl)phenyl]thiourea and a polystyrene-bound analogue. The reactions are broadly applicably (also on preparative scale), in particular, to acid-sensitive substrates such as aldol products, hydroxy esters, acetals, silyl-protected alcohols, and cyanohydrins. The catalytic efficiency is truly remarkably with turnover numbers of 100,000 and turnover frequencies of up to 5700 h-1 at catalyst loadings down to 0.001 mol%. The computationally supported mechanistic interpretation emphasizes the hydrogen bond assisted heterolysis of the alcohol and concomitant preferential stabilization of the oxyanion hole in the transition state. Georg Thieme Verlag Stuttgart.
- Kotke, Mike,Schreiner, Peter R.
-
p. 779 - 790
(2008/01/03)
-
- Tetrahydropyranylation of alcohols and phenols using the synergistic catalyst system, copper(II) chloride-acetic acid
-
Copper(II) chloride-acetic acid was found to be an efficient synergistic catalytic system for the tetraphydropyranylation of various alcohols and phenols in high yields at room temperature in short reaction times. Springer-Verlag 2007.
- Wang, Min,Song, Zhi-Guo,Jiang, Heng,Gong, Hong
-
p. 599 - 602
(2008/02/03)
-
- Parallel synthesis in an EOF-based micro reactor
-
We present herein a micro reactor set-up that enables parallel syntheses to be performed under electroosmotic flow conditions. The Royal Society of Chemistry.
- Wiles, Charlotte,Watts, Paul
-
p. 4928 - 4930
(2008/09/17)
-
- Ruthenium(III) acetylacetonate [Ru(acac)3] - An efficient chemoselective catalyst for the tetrahydropyranylation (THP) of alcohols and phenols under solvent-free conditions
-
A catalytic amount of ruthenium(III) acetylacetonate (2 mol%) [Ru(acac)3] enables solvent-free tetrahydropyranylation of different types of alcohols and phenols at ambient temperature in moderate to excellent yields. Notably, selective monoprotection of diols can be achieved chemoselectively. Furthermore, the catalyst could be recovered and reused if necessary.
- Varala, Ravi,Adapa, Srinivas R.
-
p. 1174 - 1179
(2007/10/03)
-
- Efficient role of ionic liquid (bmim)HSO4 as novel catalyst for monotetrahydropyranylation of diols and tetrahydropyranylation of alcohols
-
A simple procedure for the monotetrahydropyranylation of diols and alcohols, in excellent to moderate yields, has been reported using a catalytic amount of the acidic ionic liquid, 1-butyl-3-methylimidazolium hydrogensulphate (bmim)HSO4 under microwave and ultrasonic irradiation. Results have been compared with those obtained by reactions in the absence of these energies, and effectiveness of the recycled ionic liquid has also been studied. Copyright Taylor & Francis Group, LLC.
- Singh, Jasvinder,Gupta, Neeraj,Kad, Goverdhan L.,Kaur, Jasamrit
-
p. 2893 - 2900
(2007/10/03)
-
- PRODUCTION PROCESS OF TETRAHYDROPYRAN COMPOUND AND TETRAHYDROPYRAN COMPOUND PRODUCED BY THE PRODUCTION PROCESS
-
The invention provides a production process of a tetrahydropyran compound, characterized by allowing 3,4-dihydro-2-alkoxy-2H-pyran compound or tetrahydro-2-alkoxy-2H-pyran compound which can be easily prepared through reaction between acrolein and alkylvinylether, with hydrogen in the presence of a catalyst containing an element of Groups VIII to X under acidic condition. The production process of the invention is useful for production of Grignard reaction solvent or polymer solvent and intermediate of organic compound.
- -
-
Page/Page column 22; 28
(2008/06/13)
-
- Simple and facile tetrahydropyranylation of alcohols by use of catalytic amounts of benzyltriphenylphosphonium tribromide
-
An efficient and mild system for protection of a variety of alcohols with 3,4-dihydro-2H-pyran (DHP) in the presence of catalytic amounts of benzyltriphenyl-phosphonium tribromide (BTPTB) (1) gives the corresponding tetrahydropyan ethers (ROTHP) in dichloromethane. The experimental procedure is simple, and the products are straightforwardly isolated in high to excellent yields. Copyright Taylor & Francis, Inc.
- Hajipour,Pourmousavi,Ruoho
-
p. 2889 - 2894
(2007/10/03)
-
- A novel photoinduced reduction system of low-valent samarium species: Reduction of organic halides and chalcogenides, and its application to carbonylation with carbon monoxide
-
Visible light irradiation is found to enhance the reducing ability of samarium diiodide (SmI2) dramatically. Organic halides (RCl, RBr, RI) and chalcogenides (RSPh, RSePh, RTePh) are smoothly reduced to the corresponding hydrocarbons by using this SmI2-hv system. The photoactivation can be also applied to ytterbium diiodide (YbI2) successfully. When the reduction of alkyl chlorides (RCl) by using the SmI 2-hv system is conducted under the pressure of carbon monoxide, unsymmetric ketones (RC(O)CH2R) are obtained as carbonylating products. A mechanistic pathway may involve the formation of acylsamarium species (RC(O)SmI2), which undergo dimerization, followed by reduction with SmI2, leading to the unsymmetric ketones.
- Sumino, Yukihito,Harato, Nami,Tomisaka, Yuri,Ogawa, Akiya
-
p. 10499 - 10508
(2007/10/03)
-
- Solvent-Free Tetrahydropyranylation of Alcohols with Sulfamic Acid as Reusable Catalyst
-
An efficient H2NSO3H-catalyzed solvent-free tetrahydropyranylation of various alcohols at room temperature was investigated. The features of mild conditions, cost-efficient catalyst, simple work-up, and the recyclability of the catalyst were displayed in this article.
- Wang, Bo,Yang, Li-Ming,Suo, Ji-Shuan
-
p. 3929 - 3934
(2007/10/03)
-
- Potassium dodecatangestocobaltate trihydrate (K5CoW12O40·3H2O): A mild and efficient catalyst for the tetrahydropyranylation of alcohols and their detetrahydropyranylation
-
A simple, mild and effective method for tetrahydropyranylation of a variety of alcohols and cleavage of their tetrahydropyranyl ethers at ambient temperature in the presence of K5CoW12O40·3H2O as the catalyst with high turnovers is described.
- Habibi, Mohammad H.,Tangestaninejad, Shahram,Mohammadpoor-Baltork, Iraj,Mirkhani, Valiollah,Yadollahi, Bahram
-
p. 2851 - 2853
(2007/10/03)
-
- Photoinduced reduction of group 16 heteroatom compounds with the aid of samarium diiodide
-
A novel photoinduced reduction of group 16 heteroatom compounds such as organic selenides, tosylates, and tellurides has been developed. In particular, organic selenides, which can not be reduced with SmI2 in the dark (or even in the presence of HMPA), undergo reductive cleavage efficiently by using the SmI2-hv system.
- Ogawa, Akiya,Ohya, Syoji,Doi, Mikio,Sumino, Yukihito,Sonoda, Noboru,Hirao, Toshikazu
-
p. 6341 - 6342
(2007/10/03)
-
- Bis [trinitratocerium (IV)] chromate [ce(NO3)2 Cro4] and tris [trinitratocerium (IV)] paraperiodate [(No3)3Ce]3 H2IO6. Two mild and efficient catalysts for tetrahydrop
-
The tetrahydropyranyl derivatives of variety of alcohols are efficiently prepared in the presence of catalytic amounts of [Ce(NO3)2CrO4] and [(NO3)3 Ce]3 H21O6 in mild
- Oskooie,Abaszadeh,Zamani,Heravi
-
p. 2281 - 2285
(2007/10/03)
-
- Functionalized aliphatic P2/P2' analogs of HIV-1 protease inhibitor DMP323
-
A series of analogs of HIV protease inhibitor DMP323 containing functionalized aliphatic P2/P2' groups was prepared and evaluated for HIV protease inhibition and antiviral activity in a cell-based assay. Asymmetric compounds with a 5-hydroxypentyl substituent at P2 and a benzylic substituent at P2' showed increased potency over the corresponding symmetrically substituted analogs.
- Smallheer, Joanne M.,McHugh, Robert J.,Chang, Chong-Hwan,Kaltenbach III, Robert F.,Worley, Tabitha V.,Klabe, Ronald M.,Bacheler, Lee T.,Rayner, Marlene M.,Erickson-Viitanen, Susan,Seitz, Steven P.
-
p. 1365 - 1370
(2007/10/03)
-
- Envirocat EPZG as a new heterogenous catalyst for the solvent-free tetrahydropyranylation of alcohols and phenols
-
Envirocat EPZG was used as a solid supported acid catalyst for tetrahydropyranylation of alcohols and phenols in the absence of a solvent. This new method is rapid, efficient and convenient giving the corresponding products in high yields and purity.
- Bandgar,Jagtap,Aghade,Wadgaonkar
-
p. 2211 - 2215
(2007/10/02)
-
- A versatile ruthenium catalyst for the tetrahydropyranylation of alcohols and phenols
-
The tetrahydropyranyl derivatives of alcohols and phenols are efficiently prepared in the presence of catalytic amounts of [Ru(CH3CN)3(triphos)](OTf)2 (triphos = CH3C(CH2PPh2)3) under mild conditions, in good to excellent yields.
- Ma,Venanzi
-
p. 5269 - 5272
(2007/10/02)
-
- Stereoselective synthesis of alkenyl alcohols using dissolving metal(Ca,Na) reduction
-
Use of the calcium-ethylenediamine and sodium-liquid ammonia reduction systems for the ring opening of dihydropyran derivatives was studied. (Z)-Alkenyl alcohols and (E)-alkenyl alcohols were stereoselectively synthesized respectively.
- Zhou,Lu,Huang,Wu
-
p. 435 - 441
(2007/10/02)
-
- COBALT (II) CHLORIDE CATALYSED ADDITION OF ALCOHOLS ON VINYL ETHERS: A CONVENIENT SYNTHESIS OF MIXED ACETALS
-
Hydroxyl compounds readily add to Vinyl ethers in presence of a catalytic amount of Cobalt (II) Chloride, to give high yields of mixed acetals.
- Igbal, Javed,Srivastava, Rajeev Ranjan,Gupta, Kiran Bala,Khan, M. Amin
-
p. 901 - 906
(2007/10/02)
-