71264-85-2Relevant academic research and scientific papers
Copper-catalysed cyanoalkylative cycloetherification of alkenes to 1,3-dihydroisobenzofurans: development and application to the synthesis of citalopram
Ha, Tu M.,Wang, Qian,Zhu, Jieping
, p. 11100 - 11103 (2016)
A copper-catalysed cyanoalkylative cycloetherification of alkenes was developed. Heating a solution of substituted (2-vinylphenyl)methanol in MeCN/MeOH (v/v 7/3) in the presence of a catalytic amount of copper(ii) tetrafluoroborate hydrate [Cu(BF4)2·6H2O], bathophenanthroline, K3PO4, BnOH and (tBuO)2 afforded 1,3-dihydroisobenzofurans (phthalanes) via formation of one C(sp3)-C(sp3) and one C(sp3)-O bonds. A concise synthesis of citalopram, a marketed anti-depressant drug, was accomplished by applying this novel synthetic transformation.
Copper-Catalyzed Enantioselective Hydroalkoxylation of Alkenols for the Synthesis of Cyclic Ethers
Chen, Dake,Berhane, Ilyas A.,Chemler, Sherry R.
, p. 7409 - 7414 (2020/06/29)
The copper-catalyzed enantioselective intramolecular hydroalkoxylation of unactivated alkenes for the synthesis of tetrahydrofurans, phthalans, isochromans, and morpholines from 4- and 5-alkenols is reported. The substrate scope is complementary to existing enantioselective alkene hydroalkoxylations and is broad with respect to substrate backbone and alkene substitution. The asymmetric induction and isotopic labeling studies support a polar/radical mechanism involving enantioselective oxycupration followed by C-[Cu] homolysis and hydrogen atom transfer. Synthesis of the antifungal insecticide furametpyr was accomplished.
Metal-Free Arylation-Lactonization Sequence of γ-Alkenoic Acids Using Anilines as Aryl Radical Precursors
Felipe-Blanco, Diego,Gonzalez-Gomez, Jose C.
, p. 7735 - 7744 (2019/12/24)
The presence of salicylic acid (10 mol-%) and H2O (10 equiv.) significantly improves the arylation-lactonization sequence of γ-alkenoic acids with in situ formed diazonium salts (from bench stable anilines). The reaction is finished in less than 5 h without thermal or photochemical activation, giving access to a variety of γ,γ-disubstituted butyrolactones. The protocol is user-friendly and can be used at gram-scale or adapted to transform alkenols into phthalanes. Control experiments revealed that aryl radicals participate in the reaction and a plausible mechanism is proposed to include this and other mechanistic investigations, for the catalyzed and the background reaction.
Copper-Catalyzed Modular Amino Oxygenation of Alkenes: Access to Diverse 1,2-Amino Oxygen-Containing Skeletons
Hemric, Brett N.,Chen, Andy W.,Wang, Qiu
, p. 1468 - 1488 (2019/01/25)
Copper-catalyzed alkene amino oxygenation reactions using O-acylhydroxylamines have been achieved for a rapid and modular access to diverse 1,2-amino oxygen-containing molecules. This transformation is applicable to the use of alcohols, carbonyls, oximes, and thio-carboxylic acids as nucleophiles on both terminal and internal alkenes. Mild reaction conditions tolerate a wide range of functional groups, including ether, ester, amide, carbamate, and halide. The reaction protocol allows for starting with free amines as the precursor of O-benzoylhydroxylamines to eliminate their isolation and purification, contributing to broader synthetic utilities. Mechanistic investigations reveal the amino oxygenation reactions may involve distinct pathways, depending on different oxygen nucleophiles.
Palladium-catalyzed markovnikov terminal arylalkynes hydrostannation: Application to the synthesis of 1,1-diarylethylenes
Hamze, Abdallah,Veau, Damien,Provot, Olivier,Brion, Jean-Daniel,Alami, Mouad
supporting information; experimental part, p. 1337 - 1340 (2009/07/04)
The palladium-catalyzed hydrostannation of terminal aryla-lkynes was achieved. The regioselectivity of the H-Sn bond addition across the triple bond was found to be controlled by an ortho substituent on the aromatic ring, whatever its electronic nature, to give exclusively α-branched vinylstan-nanes 2 in accordance with Markovnikov's rule. Subsequent Stille cross-coupling reaction of 2 with a variety of aryl halides readily provided, in moderate to good yields, a family of functionalized 1,1-diarylethylenes 1.
Heck-mediated synthesis and photochemically induced cyclization of [2-(2-styrylphenyl)ethyl]carbamic acid ethyl esters and 2-styryl-benzoic acid methyl esters: Total synthesis of naphtho[2,1f]isoquinolines (2-azachrysenes)
Pampín, M. Carme,Estévez, Juan C.,Estévez, Ramón J.,Maestro, Miguel,Castedo, Luis
, p. 7231 - 7243 (2007/10/03)
We describe two new closely related total syntheses of naphtho[2,1-f]isoquinolines. The first synthesis consists of a Heck coupling reaction between trifluoromethanesulfonic acid 2-(2-ethoxycarbonylaminoethyl)phenyl esters and styrenes to give [2-(2-styrylphenyl)ethyl]carbamic acid ethyl esters. These compounds cyclize to give (2-phenanthren-1-yl-ethyl)carbamic acid ethyl esters, from which 2-azachrysenes can be obtained in a three-step sequence. The second synthesis includes a new total synthesis of 2-styrylbenzoic acid methyl esters by Heck coupling of methyl o-iodobenzoates to styrenes, followed by the transformation of the resulting benzoic acid derivatives into phenanthrene-1-carboxylic acid methyl esters and then into the target compounds by a six-step sequence including a Bischler-Napieralski cyclization.
Palladium-mediated total synthesis of 2-styrylbenzoic acids: A general route to 2-azachrysenes
Pampín, Carme,Estévez, Juan C,Castedo, Luis,Estévez, Ramón J
, p. 4551 - 4553 (2007/10/03)
We describe a new total synthesis of 2-styrylbenzoic acids by Heck coupling of methyl o-iodobenzoates to styrenes. Additionally, in the first general synthesis of naphtho[2,1-f]isoquinolines, these acids were transformed into phenanthrenoic acids and then
