85157-61-5Relevant academic research and scientific papers
Facile Access to Diverse Libraries of Internal Alkynes via Sequential Iododediazoniation/Decarboxylative Sonogashira Reaction in Imidazolium ILs without Ligand or Additive
Prabhala, Pavankumar,Savanur, Hemantkumar M.,Kalkhambkar, Rajesh G.,Laali, Kenneth K.
, p. 2061 - 2064 (2019/03/07)
Convenient access to diverse libraries of internal alkynes via decarboxylative Sonogashira reaction of alkynyl-carboxylic acids with iodoarenes, employing imidazolium-ILs as solvent, along with piperidine-appended imidazolium [PAIM][NTf2] as task-specific basic IL is demonstrated, without the need for any ligand or additive. The feasibility to perform these reactions by sequential one-pot iododediazoniation/decarboxylative Sonogashira reaction is also shown, and the scope of the methods is underscored by providing 29 examples. The potential for recycling and reuse of the IL solvent is also examined.
Catalyst-dependent divergent synthesis of pyrroles from 3-alkynyl imine derivatives: A noncarbonylative and carbonylative approach
Chen, Gen-Qiang,Zhang, Xiao-Nan,Wei, Yin,Tang, Xiang-Ying,Shi, Min
supporting information, p. 8492 - 8497 (2014/08/18)
A novel Ru0- and RhI-catalyzed noncarbonylative and carbonylative cycloisomerization of readily available 3-alkynyl imine derivatives has been developed to provide 3,4-fused or nonfused pyrrole derivatives efficiently in moderate to
Rhodium-catalyzed carbonylative skeleton rearrangement of 1,4-enynes tethered by a cyclopropane group
Chen, Gen-Qiang,Tang, Xiang-Ying,Shi, Min
supporting information, p. 2311 - 2315 (2015/08/06)
The carbonylative skeleton rearrangement of 1,4 enynes tethered by a cyclopropane group proceeded smoothly in the presence of [Rh(CO)2Cl]2 under CO atmosphere to give the corresponding 1,2,4,5,6,7-hexahydrocyclopenta[a]inden-3(3bH)-o
Iron-catalyzed cyclopropanation in 6 M KOH with in situ generation of diazomethane
Morandi, Bill,Carreira, Erick M.
scheme or table, p. 1471 - 1474 (2012/07/13)
Diazomethane is a common and versatile reagent in organic synthesis whose broader use is generally impeded by its explosiveness and toxicity. Here we report that a simple iron porphyrin complex catalyzes the cyclopropanation of styrenes, enynes, and dienes under the demanding conditions [aqueous 6 molar potassium hydroxide (KOH) solution, open to air] necessary for the in situ generation of diazomethane from a water-soluble diazald derivative. A biphasic reaction medium arising from the immiscibility of the olefin substrates with water appears essential to the overall efficiency of the process. The work we describe highlights an approach to catalysis with untoward reactive intermediates, in which the conditions for their generation under operationally safe regimes dictate catalyst selection.
Palladium-catalyzed cross-coupling of electron-poor terminal alkynes with arylboronic acids under ligand-free and aerobic conditions
Zhou, Ming-Bo,Wei, Wen-Ting,Xie, Ye-Xiang,Lei, Yong,Li, Jin-Heng
experimental part, p. 5635 - 5642 (2010/11/04)
Palladium-catalyzed cross-coupling reaction of terminal alkynes with arylboronic acids has been described. In the presence of Pd(OAc)2 and Ag2O, a variety of terminal alkynes, including electron-poor terminal alkynes, smoothly underwent the reaction with numerous boronic acids to afford the corresponding internal alkynes in moderate to good yields. Moreover, this methodology was applied to the synthesis of 1H-isochromenes and diynes. It is noteworthy that the reaction proceeds under ligand-free and relative lower loading Pd conditions, and the maximal TONs (turnover numbers) of the reaction are up to 720,000.
Gold(l)-catalyzed ring expansions of unactivated alkynylcyclopropanes to (E)-2-alkylidenecyclobutanamines in the presence of sulfonamides
Ye, Siyu,Yu, Zhi-Xiang
supporting information; experimental part, p. 804 - 807 (2010/04/06)
(Chemical Equation Presented) The ring expansion of cyclopropane derivatives provides a powerful method to construct synthetically useful four-membered carbocycles. Herein, a new type of gold(l)-catalyzed ring expansion of an unactivated alkynylcyclopropane/sulfonamide trapping strategy to (E)-2-alkylidenecyclobutanamines was described. The reaction tolerates a range of aryl and alkyl substituents with moderate to good yields.
One-pot procedure for the synthesis of N-substituted 2-(arylmethyl) pyrrolidines from l-aryl-2-cyclopropylalkynes and primary amines by a hydroamination/cyclopropylimine rearrangement/reduction sequence
Graebe, Kerstin,Zwafelink, Bjoern,Doye, Sven
experimental part, p. 5565 - 5575 (2010/02/28)
A one-pot procedure for the synthesis of N-substituted 2(arylmethyl) pyrrolidines from l-aryl-2-cyclopropylalkynes and primary amines is presented. The procedure proceeded first through an [Ind2TiMe 2]-catalyzed regioselective hydroa
Vinylcations, 39. Zinc Chloride Catalysed Addition of Hydrogen Chloride to Cyclopropylalkynes
Hanack, Michael,Weber, Erhard
, p. 777 - 797 (2007/10/02)
Zinc chloride catalysed addition of hydrogen chloride to 1-cyclopropylalkynes 5a-e (R = CH3, c-C3H5, phenyl, p-tolyl, 4-methoxyphenyl) is studied and the results are compared with those of the addition of HCl/ZnCl2 to several substituted arylalkynes 10a-h.Thus, the alkynes are reacted with HCl/ZnCl2 in dichloromethane and the reaction products are investigated also with respect to their stereochemistry.All alkynes yield predominantly the direkt hydrogen chloride addition products.The 1-cyclopropylalkynes 5a-d give (E)-1-chloro-1-cyclopropyl-1-alkenes 15, and (E)-1-chloro-2-cyclopropyl-1-(4-methoxyphenyl)ethene (16e) is obtained as the major product from 5e (R = 4-CH3OC6H4).Moreover, ring opening to homoallenyl chlorides 19 and, as a side reaction, formation of the ketones 17 and 18 by the addition of water are observed.In a secondary addition reaction, the dichlorides 20 are also obtained by homoallyl rearrangement.The arylalkynes 10a-g react preferentially with formation of (E)-1-aryl-1-chloroalkenes 21.Relative rates are obtained by inter- and intramolecular competition reactions of the alkynes 23 and 5b-e with HCl/ZnCl2 showing the order of stabilization by substituents of the intermediate vinyl cation 2 to be 4-ClC6H4 E2 mechanism.The preferential formation of the addition products E-15, E-16, and E-21 is attributed to a syn-vinyl cation ion pair and to steric approach control of the β-substituents in the vinyl cation intermediate 2.
