594-56-9Relevant academic research and scientific papers
Experimental and Computational Studies of Palladium-Catalyzed Spirocyclization via a Narasaka-Heck/C(sp3or sp2)-H Activation Cascade Reaction
Wei, Wan-Xu,Li, Yuke,Wen, Ya-Ting,Li, Ming,Li, Xue-Song,Wang, Cui-Tian,Liu, Hong-Chao,Xia, Yu,Zhang, Bo-Sheng,Jiao, Rui-Qiang,Liang, Yong-Min
supporting information, p. 7868 - 7875 (2021/05/27)
The first synthesis of highly strained spirocyclobutane-pyrrolines via a palladium-catalyzed tandem Narasaka-Heck/C(sp3 or sp2)-H activation reaction is reported here. The key step in this transformation is the activation of a δ-C-H bond via an in situ generated σ-alkyl-Pd(II) species to form a five-membered spiro-palladacycle intermediate. The concerted metalation-deprotonation (CMD) process, rate-determining step, and energy barrier of the entire reaction were explored by density functional theory (DFT) calculations. Moreover, a series of control experiments was conducted to probe the rate-determining step and reversibility of the C(sp3)-H activation step.
Organic base-catalysed solvent-tuned chemoselective carbotrifluoromethylation and oxytrifluoromethylation of unactivated alkenes
Yang, Ning-Yuan,Li, Zhong-Liang,Ye, Liu,Tan, Bin,Liu, Xin-Yuan
supporting information, p. 9052 - 9055 (2016/07/21)
An unprecedented and efficient organic base-catalysed highly chemoselective carbo- and oxytrifluoromethylation of unactivated alkenes with Togni's reagent was developed. The switchable chemoselectivity was tuned by simply changing the organic base catalyst and solvent. Mechanistic studies indicated that a radical cyclization pathway for carbotrifluoromethylation in DMSO and a carbocation pathway for oxytrifluoromethylation in DCE were probably involved.
Asymmetric Copper-Catalyzed Carbozincation of Cyclopropenes en Route to the Formation of Diastereo- and Enantiomerically Enriched Polysubstituted Cyclopropanes
Müller, Daniel S.,Marek, Ilan
supporting information, p. 15414 - 15417 (2015/12/26)
The enantioselective synthesis of cyclopropylzinc reagents has been achieved via a copper-catalyzed carbozincation of 3,3-disubstituted cyclopropenes with diorganozinc reagents. The obtained organozinc compounds can be easily functionalized with a broad range of electrophiles, including palladium-catalyzed cross-couplings, affording highly substituted cyclopropanes. The operationally simple procedure using very low quantities of a commercially available and inexpensive copper catalyst provides a new tool for the synthesis of highly enantioenriched cyclopropanes as single diastereoisomers.
The methylation of alkenes to triptyls with dimethyl carbonate
Armitage, Gareth G.,Bonati, Matteo L. M.,Guo, Neng,Gaemers, Sander,Shabaker, John W.
, p. 370 - 374 (2013/05/21)
A series of methylating reagents: methanol, dimethylether and dimethylcarbonate, have been evaluated for their ability to methylate 2,3-dimethylbut-2-ene to yield triptyls (a mixture of triptane and triptene). The results presented highlight that dimethylcarbonate is a far superior methylating agent compared to methanol or dimethylether, providing a higher yield of triptyls.
Process for the production of hydrocarbons
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Page/Page column 4-6, (2008/06/13)
A process for the production of a hydrocarbon comprises reacting methanol, dimethyl ether, methyl acetate or mixtures thereof, with an olefin in the presence of methyl halide and/or hydrogen halide and at least one compound selected from the group consisting of ruthenium carbonyl halides, osmium carbonyl halides and mixtures thereof.
PROCESS FOR THE PRODUCTION OF A HYDROCARBON
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Page/Page column 19-20; 25-26, (2008/06/13)
A process for the production of a hydrocarbon which comprises contacting, in a reactor, methanol and/or dimethyl ether with a catalyst comprising a metal halide, such as a zinc halide, in which the methanol and/or dimethyl ether is contacted with the catalyst in the presence of at least one phosphorus compound having at least one P-H bond.
On the mechanism of the conversion of methanol to 2,2,3-trimethylbutane (triptane) over zinc iodide
Bercaw, John E.,Diaconescu, Paula L.,Grubbs, Robert H.,Kay, Richard D.,Kitching, Sarah,Labinger, Jay A.,Li, Xingwei,Mehrkhodavandi, Parisa,Morris, George E.,Sunley, Glenn J.,Vagner, Patrick
, p. 8907 - 8917 (2007/10/03)
Methanol is converted to a mixture of hydrocarbons by reaction with zinc iodide at 200 °C with one highly branched alkane, 2,2,3-trimethylbutane (triptane), being obtained in surprisingly high selectivity. Mechanistic studies implicate a two-stage process, the first involving heterogeneously catalyzed formation of a carbon-carbon-bonded species, probably ethylene, that undergoes homogeneously catalyzed sequential cationic methylation to higher hydrocarbons. The first stage can be bypassed by addition of olefins, higher alcohols, or arenes, which act as initiators. Rationales for the particular activity of zinc iodide and for the selectivity to triptane are proposed.
PYRIDOPYRAZINES FOR COMBATTING PHYTOPATHOGENIC FUNGI
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Page/Page column 11-12, (2008/06/13)
The compounds of the general formula (I) wherein R, R1, R2, R8, and R9 are defined as set forth in the specification.
Novel, Very Strong, Uncharged Auxiliary Bases; Design and Synthesis of Monomeric and Polmer-Bound Triaminoiminophosphorane Bases of Broadly Varied Steric Demand
Schwesinger, Reinhard,Willaredt, Juergen,Schlemper, Helmut,Keller, Manfred,Schmitt, Dieter,Fritz, Hans
, p. 2435 - 2454 (2007/10/02)
The synthesis and properties of a number of very strong iminophosphorane bases up to an extremely high level of steric hindrance are described.They cover a range of ca. 4 pK units in basicity and a range of more than 11 orders of magnitude in their rates of methylation with methyl iodide.Most of the systems are readily prepared in up to molar quantities, conveniently recovered from their salts and are of high chemical and thermal stability.Crystal structures were determined in order to parametrize a force field, which is utilized in molecular modeling studies offering a rationalization of the observed differences in steric hindrance and basicity.Depending on the degree of steric protection of the basic center, these novel bases are proposed as unprecedented, versatile auxiliary bases in E2 eliminations and in reactions involving deprotonation in the presence of more or less strong electrophiles. - Key Words: Uncharged auxiliary bases / Triaminoiminophosphorane bases / Deprotonation / Hindered bases / Polymeric bases
