118220-81-8Relevant articles and documents
Chiral vinyl dioxazaborocines in synthesis: Asymmetric synthesis of 5- substituted Δ2-isoxazolines via nitrile oxide cycloaddition
Davies, Christopher D.,Marsden, Stephen P.,Stokes, Elaine S. E.
, p. 8513 - 8516 (1998)
Vinyl dioxazaborocines 1a-c have been subjected to 1,3-dipolar cycloadditions with benzonitrile oxide. The products are enantiomerically enriched 5-substituted Δ2-isoxazolines 2a-c.
Study on the "tin-ene" reaction of α-bromoacetophenone and metallic tin with aldehydes
Zhou, Jing-Yao,Jia, Yu,Shao, Qiu-Yi,Wu, Shi-Hui
, p. 769 - 775 (1996)
β-hydroxy ketones were obtained in good yields by the "tin-ene" reactions of α-bromoacetophenone and metallic tin with aldehydes.
A novel one-pot Reformatsky type reaction via bismuth salt in aqueous media
Shen, Zhen,Zhang, Jinqi,Zou, Huixian,Yang, Minmin
, p. 2733 - 2736 (1997)
In the presence of bismuth(III)chloride-metallic aluminum, α-halo carbonyl compounds react with aldehydes in water under mild conditions to give B-hydroxy carbonyl compounds with stereoselectivity in good yields.
Gold-Catalyzed Hydroamination of Propargylic Alcohols: Controlling Divergent Catalytic Reaction Pathways to Access 1,3-Amino Alcohols, 3-Hydroxyketones, or 3-Aminoketones
Laserna, Victor,Porter, Michael J.,Sheppard, Tom D.
, p. 11391 - 11406 (2019/09/30)
A versatile approach to the valorization of propargylic alcohols is reported, enabling controlled access to three different products from the same starting materials. First, a general method for the hydroamination of propargylic alcohols with anilines is described using gold catalysis to give 3-hydroxyimines with complete regioselectivity. These 3-hydroxyimines can be reduced to give 1,3-amino alcohols with high syn selectivity. Alternatively, by using a catalytic quantity of aniline, 3-hydroxyketones can be obtained in high yield directly from propargylic alcohols. Further manipulation of the reaction conditions enables the selective formation of 3-aminoketones via a rearrangement/hydroamination pathway. The utility of the new chemistry was exemplified by the one-pot synthesis of a selection of N-arylpyrrolidines and N-arylpiperidines. A mechanism for the hydroamination has been proposed on the basis of experimental studies and density functional theory calculations.
Strong Lewis acid air-stable cationic titanocene perfluoroalkyl(aryl) sulfonate complexes as highly efficient and recyclable catalysts for C-C bond forming reactions
Li, Ningbo,Wang, Jinying,Zhang, Xiaohong,Qiu, Renhua,Wang, Xie,Chen, Jinyang,Yin, Shuang-Feng,Xu, Xinhua
supporting information, p. 11696 - 11708 (2014/07/22)
A series of strong Lewis acid air-stable titanocene perfluoroalkyl(aryl) sulfonate complexes Cp2Ti(OH2)2(OSO 2X)2·THF (X = C8F17, 1·THF; X = C4F9, 2·H2O· THF; X = C6F5, 3) were successfully synthesized by the treatment of Cp2TiCl2 with C8F 17SO3Ag, C4F9SO3Ag and C6F5SO3Ag, respectively. In contrast to well-known titanocene bis(triflate), these complexes showed no change in open air over three months. TG-DSC analysis showed that 1·THF, 2·H 2O·THF and 3 were thermally stable at 230 °C, 220°C and 280°C, respectively. Conductivity measurements showed that these complexes underwent ionic dissociation in CH3CN solution. X-ray analysis results confirmed that 2·H2O·THF and 3 were cationic. ESR spectra showed that the Lewis acidity of 1·THF (1.06 eV) was higher than that of Sc3+ (1.00 eV) and Y3+ (0.85 eV). UV/Vis spectra showed a significant red shift due to the strong complex formation between 10-methylacridone and 2·H2O·THF. Fluorescence spectra showed that the Lewis acidity of 2 (λem = 477 nm) was higher than that of Sc3+ (λem = 474 nm). These complexes showed high catalytic ability in various carbon-carbon bond forming reactions. Moreover, they show good reusability. Compared with 1·THF, 2·H2O·THF and 3 exhibit higher solubility and better catalytic activity, and will find broad applications in organic synthesis. This journal is the Partner Organisations 2014.
P(PhCH2NCH2CH2)3N catalysis of Mukaiyama aldol reactions of aliphatic, aromatic, and heterocyclic aldehydes and trifluoromethyl phenyl ketone
Chintareddy, Venkat Reddy,Wadhwa, Kuldeep,Verkade, John G.
experimental part, p. 8118 - 8132 (2010/02/28)
(Chemical Equation Presented) Herein we find that proazaphosphatrane 1c is a very efficient catalyst for Mukaiyama aldol reactions of aldehydes with trimethylsilyl enolates in THF solvent. Only the activated ketone 2,2,2-trifluoroacetophenone underwent clean aldol product formation with a variety of trimethylsilyl enolates under similar conditions as the aldehydes. The reactions were carried out at room temperature using (1-methoxy-2-methyl-1- propenyloxy)trimethylsilane, whereas the temperature was -15 °C in the case of 1-phenyl-1-(trimethylsilyloxy)ethylene. The reaction conditions are mild and operationally simple, and a variety of aryl functional groups, such as nitro, amino, ester, chloro, trifluoromethyl, bromo, iodo, cyano, and fluoro groups, are tolerated. Product yields are generally better than or comparable to those in the literature. 1-Phenyl-1-(trimethylsilyloxy)ethylene, 1-(trimethylsilyloxy) cyclohexene, and 2-(trimethylsilyloxy)furan underwent clean conversion to β-hydroxy carbonyl compounds under our reaction conditions. In the case of bulky (2,2-dimethyl-1-methylenepropoxy)trimethylsilane, only α,β-unsaturated esters were isolated. Heterocyclic aldehydes, such as pyridine-2-carboxaldehyde, benzofuran-2-carboxaldehyde, benzothiophene-2- carboxaldehyde, and 1-methyl-2-imidazolecarboxaldehyde, gave good yields of Mukaiyama products. An optimized synthesis for the catalyst 1c is also reported herein. 2009 American Chemical Society.
Aldol reactions of α-bromoalkyl phenyl ketones and aldehydes with tin(IV) iodide and tetrabutylammonium iodide
Masuyama, Yoshiro,Ohtsuka, Masaru,Kondo, Ayako
, p. 3346 - 3348 (2008/09/18)
Aldol reactions of α-bromoacetophenone and aldehydes in dichloromethane produced the corresponding E-α,β-unsaturated ketones at 25 °C with one equimolar amount of tin(IV) iodide, one equimolar amount of tetrabutylammonium iodide and one equimolar amount of N,N- diisopropylethylamine, and produced the corresponding β-hydroxy ketones at -80 °C with one equimolar amount of tin(IV) iodide and two equimolar amounts of tetrabutylammonium iodide. Using one equimolar amount of tin(IV) iodide and two equimolar amounts of tetrabutylammonium iodide at -80 °C in dichloromethane, α-bromopropiophenone reacted with aldehydes to afford the corresponding syn-α-methyl-β-hydroxy ketones selectively. Georg Thieme Verlag Stuttgart.
BCl3- and TiCl4-mediated reductions of β-hydroxy ketones
Sarko, Christopher R.,Collibee, Scott E.,Knorr, Allison L.,DiMare, Marcello
, p. 868 - 873 (2007/10/03)
Syn-selective reduction protocols for β-hydroxy ketones are described exploiting the intermediacy of titanium and boron chelates derived from TiCl4 and BCl3, respectively. Reductions are conducted at -78°C in CH2Cl2/
FACILE ROUTES TO BORON ENOLATES. Et3B-MEDIATED REFORMATSKY TYPE REACTION AND THREE COMPONENTS COUPLING REACTION OF ALKYL IODIDES, METHYL VINYL KETONE, AND CARBONYL COMPOUNDS
Nozaki, Kyoko,Oshima, Koichiro,Utimoto, Kiitiro
, p. 1041 - 1044 (2007/10/02)
Reaction of α-bromoketones with Ph3SnH in the presence of Et3B provides boron enolates which react with carbonyl compounds to give β-hydroxyketones in good yields.Et3B-induced Reformatsky type reaction of α-iodoketones with an aldehyde or ketone proceeds without Ph3SnH.
