91763-35-8Relevant academic research and scientific papers
Rhodium-Catalyzed Alkenylation of Toluene Using 1-Pentene: Regioselectivity to Generate Precursors for Bicyclic Compounds
Liebov, Nichole S.,Zhu, Weihao,Chen, Junqi,Webster-Gardiner, Michael S.,Schinski, William L.,Gunnoe, T. Brent
supporting information, p. 3844 - 3851 (2019/10/16)
Rhodium catalysts for arene alkenylation reported by our group (e.g., Science 2015, 348, 421; J. Am. Chem. Soc. 2017, 139, 5474; J. Am. Chem. Soc. 2018, 140, 17007) have demonstrated selectivity for 1-aryl alkenes over y-aryl alkenes (y > 1). This selectivity is notable because 1-aryl alkenes or 1-aryl alkanes cannot be generated using acid-based Friedel-Crafts arene alkylation or acidic zeolite catalysts. Herein, we report the extension of Rh arene alkenylation catalysis to generate 1-tolyl-1-pentenes, which are potential precursors for bicyclic compounds. The olefin concentration, copper(II) oxidant identity and concentration, reaction temperature, and rhodium concentration for the alkenylation of toluene with 1-pentene have been optimized using [Rh(Η2-C2H4)2(μ-OAc)]2 as the catalyst precursor. The rhodium-based catalysis achieves up to 12(1):1 anti-Markovnikov selectivity for 1-tolyl-1-pentenes over 2-tolyl-2-pentenes and is selective for alkenylation in the meta and para positions.
The directing group wins over acidity: kinetically controlled regioselective lithiation for functionalization of 2-(2,4-dihalophenyl)-1,3-dithiane derivatives
Sakthivel, Shanmugam,Kothapalli, Raveendra Babu,Balamurugan, Rengarajan
, p. 1670 - 1679 (2016/02/09)
Regioselective lithiation followed by functionalization of 2-(2,4-dihalophenyl)-1,3-dithiane derivatives with different electrophiles was achieved in good to excellent yields. When the title compound is treated with n-butyl lithium, lithiation occurs selectively at the aromatic carbon having less acidic proton despite the presence of thermodynamically more acidic 1,3-dithiane proton in the same molecule. Computationally calculated pKa values of the available reactive site protons and the experimental results suggest that the regioselective lithiation in 2-(2,4-dihalophenyl)-1,3-dithiane derivatives is not governed by thermodynamic acidity rather exclusively dictated by the kinetic removal of protons due to cooperative coordination (complex induced proximity effect, CIPE) and inductive effects of the 1,3-dihalo substituents present in the aromatic ring. By employing this regioselective functionalization, diverse 1,2,3,4-tetra-substituted aromatic compounds were prepared with ease.
The carbonyl group tuned electron-deficient phosphorus ligands and their application in Rhodium catalyzed arylation to aldehydes
Yang, Jiefang,Chen, Xingyu,Wang, Zhiqian
supporting information, p. 5673 - 5675 (2015/09/15)
Acylphosphines, which could be efficiently prepared from acid chlorides and secondary phosphines, were developed as a type of carbonyl group tuned electron-deficient phosphorus ligand. They were found to be a kind of efficient ligand in Rhodium catalyzed arylation to aldehydes through accelerating the transmetalation process. Chiral acylphosphine ligands could be generated from carboxylic acids bearing the chiral framework correspondingly.
A versatile and one-pot strategy to synthesize ?±-amino ketones from benzylic secondary alcohols using N -bromosuccinimide
Guha, Somraj,Rajeshkumar, Venkatachalam,Kotha, Surya Srinivas,Sekar, Govindasamy
supporting information, p. 406 - 409 (2015/03/04)
A metal-free one-pot strategy has been developed for the first time to synthesize pharmaceutically important ?±-amino ketones from readily available benzylic secondary alcohols and amines using N-bromosuccinimide. This new reaction proceeds via three consecutive steps involving oxidation of alcohols, ?±-bromination of ketones, and nucleophilic substitution of ?±-bromo ketones to give ?±-amino ketones. Importantly, this novel one-pot greener reaction avoids direct usage of toxic and corrosive bromine. This methodology has been employed efficiently to synthesize pharmaceutically important amfepramone and pyrovalerone in a single step.
Iron-catalysed, general and operationally simple formal hydrogenation using Fe(OTf)3 and NaBH4
MacNair, Alistair J.,Tran, Ming-Ming,Nelson, Jennifer E.,Sloan, G. Usherwood,Ironmonger, Alan,Thomas, Stephen P.
, p. 5082 - 5088 (2014/07/08)
An operationally simple and environmentally benign formal hydrogenation protocol has been developed using highly abundant iron(iii) salts and an inexpensive, bench stable, stoichiometric reductant, NaBH4, in ethanol, under ambient conditions. This reaction has been applied to the reduction of terminal alkenes (22 examples, up to 95% yield) and nitro-groups (26 examples, up to 95% yield). Deuterium labelling studies indicate that this reaction proceeds via an ionic rather than radical mechanism.
A novel one-pot synthesis of secondary alcohols from esters
Chae, Min Jung,Jeon, Ah Ram,Park, Jae Kyo,An, Duk Keun
experimental part, p. 1718 - 1720 (2011/04/25)
Alkylation or vinylation by using organometallic reagents after partial reduction of carboxylic esters with LDBBA gave secondary alcohols, also involving allyl alcohols, without any isolation of intermediates in good yield (54-78%).
Alkylation of Aldehyde (Arenesulfonyl)hydrazones with Trialkylboranes
Kabalka, George W.,Maddox, John T.,Bogas, Ekaterini,Kelley, Shane W.
, p. 3688 - 3695 (2007/10/03)
(Arenesulfonyl)hydrazone derivatives of aryl aldehydes are readily alkylated by trialkylboranes in the presence of base to generate new organoboranes that may be converted to the corresponding substituted alkanes or alcohols depending upon the reaction conditions chosen. Both tosyl- and trisylhydrazone derivatives can be utilized in the reaction, which tolerates a variety of functional groups, making it a versatile alternative to both the Grignard and Suzuki-coupling reactions.
A facile one-pot synthesis of alkylarylcarbinols from α,α-dichloroarylmethanes and trialkylboranes in the presence of magnesium or lithium
Li, Nan-Sheng,Yu, Su,Kabalka, George W.
, p. 101 - 105 (2007/10/03)
α-Chlorobenzylmagnesium chloride or α-chlorobenzyllithium generated from α,α-dichloroarylmethane and magnesium or lithium, reacts in situ with trialkylboranes in THF at room temperature to produce the corresponding alkylarylcarbinols in good yields after oxidation with sodium perborate.
Alkylation of α,α-dichloroarylmethane with trialkylboranes: Synthesis of alkylarylcarbinols
Kabalka,Kabalka, George W.,Li,Nan-Sheng, Li,Yu,Su, Yu
, p. 8545 - 8548 (2007/10/02)
The alkylation of α,α-dichloroarylmethane with trialkylboranes occurs readily in the presence of t-butyllithium at -78°C. The reaction affords the corresponding alkylarylcarbinols in good yields after oxidation with sodium perborate.
A Facile Alkylation of Aryl Aldehyde Tosylhydrazone with Trialkylboranes
Kabalka, George W.,Maddox, John T.,Bogas, Ekaterini
, p. 5530 - 5531 (2007/10/02)
Trialkylboranes readily alkylate aryl aldehyde tosylhydrazones to produce either the corresponding arylalkane or aryl alcohol in excellent yields.
