- Asymmetric Hydrogenation of Aryl Perfluoroalkyl Ketones Catalyzed by Rhodium(III) Monohydride Complexes Bearing Josiphos Ligands
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The asymmetric hydrogenation of 2,2,2-trifluoroacetophenones and aryl perfluoroalkyl ketones was developed using a unique, well-defined chloride-bridged dinuclear rhodium(III) complex bearing Josiphos-type diphosphine ligands. These complexes were prepared from [RhCl(cod)]2, Josiphos ligands, and hydrochloric acid. As catalyst precursors, they allow for the efficient and enantioselective synthesis (up to 99 % ee) of chiral secondary alcohols with perfluoroalkyl groups. This system does not require an activating base for the hydrogenation of 2,2,2-trifluoroacetophenones. Additionally, the enantioselective C=O hydrogenations of 2-phenyl-3-(haloacetyl)-indoles, a class of privileged structures in medicinal chemistry, is reported for the first time.
- Brüning, Fabian,Nagae, Haruki,K?ch, Daniel,Mashima, Kazushi,Togni, Antonio
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supporting information
p. 10818 - 10822
(2019/07/31)
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- Pesticidal compositions and processes related thereto
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This document discloses molecules having the following formula (“Formula One”): and processes associated therewith.
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Page/Page column 45-46; 132
(2016/01/09)
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- PESTICIDAL COMPOSITIONS AND PROCESSES RELATED THERETO
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This disclosure relates to the field of molecules having pesticidal utility against pests in Phyla Nematoda, Arthropoda, and/or Mollusca, processes to produce such molecules and intermediates used in such processes, compositions containing such molecules, and processes of using such molecules against such pests. These molecules may be used, for example, as nematicides, acaricides, insecticides, miticides, and/or molluscicides. This document discloses molecules having the following formula (“Formula One”).
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Paragraph 0140; 0156; 0157
(2015/12/30)
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- PESTICIDAL COMPOSITIONS AND PROCESSES RELATED THERETO
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This document discloses molecules having the following formula ("Formula One"): and processes associated therewith.
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Page/Page column 46; 47; 131
(2014/07/08)
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- PESTICIDAL COMPOSITIONS AND PROCESSES RELATED THERETO
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This document discloses molecules having the following formula (“Formula One”): and processes associated therewith.
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Paragraph 0654-0655
(2014/06/25)
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- PESTICIDAL COMPOSITIONS AND PROCESSES RELATED THERETO
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This document discloses molecules having the following formula (“Formula One”): and processes associated therewith.
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Page/Page column 71-72
(2013/02/28)
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- Oxidation of α-trifluoromethyl alcohols using a recyclable oxoammonium salt
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A simple, mild method for the oxidation of α-trifluoromethyl alcohols to trifluoromethyl ketones (TFMKs) using the oxoammonium salt 4-acetylamino-2,2,6,6-tetramethylpiperidine-1-oxoammonium tetrafluoroborate (1) is described. Under basic conditions, oxidation proceeds rapidly and affords good to excellent yields of TFMKs, without concomitant formation of the hydrate. The byproduct of the oxidation, 4-acetylamino-2,2,6,6-tetramethyl-1- piperidinyloxy (1c), is easily recovered and can be conveniently reoxidized to regenerate the oxoammonium salt.
- Kelly, Christopher B.,Mercadante, Michael A.,Hamlin, Trevor A.,Fletcher, Madison H.,Leadbeater, Nicholas E.
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p. 8131 - 8141
(2013/01/15)
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- Nonenzymatic kinetic resolution of racemic 2,2,2-trifluoro-1-aryl ethanol via enantioselective acylation
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Kinetic resolution of a series of 2,2,2-trifluoro-1-aryl ethanol with (R)-benzotetramisole as the catalyst has been investigated. The result showed that when the aryl group in the substrate was a phenyl (or a phenyl substituted by an electron-donating group) or a naphthyl (an extended phenyl) group, the system could give an s value higher than 20. Preparative KR examples demonstrated the applicability of this method in the preparation of some of enantiomerically pure 2,2,2-trifluoro-1-aryl ethanol or 2,2,2-trifluoro-1-aryl-ethyl iso-butyrate.
- Xu, Qing,Zhou, Hui,Geng, Xiaohong,Chen, Peiran
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supporting information; experimental part
p. 2232 - 2238
(2009/07/11)
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- The "tert-amino effect" in heterocyclic chemistry: synthesis of 3,1-benzoxazines and 3,1-benzothiazines
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Two different routes are described for the synthesis of the 2,2,2-trifluoro-1-ethanones 2 and 9 and their hydrates 3 and 10, respectively, via trifluoroacetylation of the N,N-dialkylanilines 1 and via a Barbier reaction of 2-fluorobenzaldehyde.These compounds were thermally converted into a mixture of cis- and trans-pyrrolo- and pyridobenzoxazines, (11: cis, 12: trans).The structure of these compounds was proven by X-ray analysis (11a) and 1H NOE difference spectroscopy.Cyclization of (R)-9b (R1 = CH3) gave predominantly one enantiomer (12f, 70percent) and in addition two diastereomers of 17a and two of 18a (total yield ca. 17percent), while cyclization of (S)-9c (R1 = CH2OCH3) gave a mixture of 12g (18percent), two diastereomers of 17b (36percent) and two diastereomers of 18b (18percent).The benzaldehyde 19a (R3 = H), acetophenone 19d (R3 = CH3), trifluoroacetophenones 19b,c (R3 = CF3) and benzophenone 19e (R3 = C6H5) reacted with Lawesson's reagent to yield exclusively the trans-pyrrolobenzothiazines 21a-e in yields of 33-77percent.Reaction of 19f (R1 = CH3, R3 = H), 19g (R1 = CH3, R3 = CF3) and 19h (R1 = CH3, R3 = CH3) with Lawesson's reagent resulted in the formation of mixtures of isomers 21-24.
- Nijhuis, W. H. N.,Verboom, W.,Harkema, S.,Reinhoudt, D. N.
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p. 147 - 160
(2007/10/02)
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