- Photocatalytic and Chemoselective Transfer Hydrogenation of Diarylimines in Batch and Continuous Flow
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A visible-light photocalytic method for the chemoselective transfer hydrogenation of imines in batch and continuous flow is described. The reaction utilizes Et3N as both hydrogen source and single-electron donor, enabling the selective reduction of imines derived from diarylketimines containing other reducible functional groups including nitriles, halides, esters, and ketones. The dual role of Et3N was confirmed by fluorescence quenching measurements, transient absorption spectroscopy, and deuterium-labeling studies. Continuous-flow processing facilitates straightforward scale-up of the reaction.
- Van As, Dean J.,Connell, Timothy U.,Brzozowski, Martin,Scully, Andrew D.,Polyzos, Anastasios
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p. 905 - 908
(2018/02/22)
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- Correction to: Photocatalytic and Chemoselective Transfer Hydrogenation of Diarylimines in Batch and Continuous Flow (Organic Letters (2018) 20:4 (905-908) DOI: 10.1021/acs.orglett.7b03565)
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Sections of Schemes 2 and 4 were omitted in error during the production process. The complete versions of Schemes 2 and 4 are shown below.(Figure Persented).Scheme 2 is corrected as follows:.
- Van As, Dean J.,Connell, Timothy U.,Brzozowski, Martin,Scully, Andrew D.,Polyzos, Anastasios
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p. 4392 - 4392
(2018/07/29)
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- Oxidative deprotection of diphenylmethylamines
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(formula presented) The diphenylmethyl amino protecting group can be efficiently removed by initial oxidation of the amine to an imine by 2,3-dichloro-5,6-dicyanobenzoquinone. The resulting imine can then be easily hydrolyzed under mildly acidic conditions. This method is particularly well suited for the preparation of α-amino phosphinates and α-amino phosphonates.
- Sampson, Peter B.,Honek, John F.
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p. 1395 - 1397
(2008/02/09)
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- Organic reactions catalyzed by methylrhenium trioxide: Dehydration, amination, and disproportionation of alcohols
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Methylrhenium trioxide (MTO) is the first transition metal complex in trace quantity to catalyze the direct formation of ethers from alcohols. The reactions are independent of the solvents used: benzene, toluene, dichloromethane, chloroform, acetone, and in the alcohols themselves. Aromatic alcohols gave better yields than aliphatic. Reactions between two different alcohols could also be used to prepare unsymmetric ethers, the best yields being obtained when one of the alcohols is aromatic. MTO also catalyzes the dehydration of alcohols to form olefins at room temperature, aromatic alcohols proceeding in better yield. When primary (secondary) amines were used as the limiting reagent, direct amination of alcohols catalyzed by MTO gave good yields of the expected secondary (tertiary) amines at room temperature. Disproportionation of alcohols to alkanes and carbonyl compounds was also observed for aromatic alcohols in the presence of MTO. On the basis of the results of this investigation and a comparison with the interaction between MTO and water, a concerted process and a mechanism involving carbocation intermediates have been suggested.
- Zhu, Zuolin,Espenson, James H.
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p. 324 - 328
(2007/10/03)
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