- Safe and Selective Nitro Group Reductions Catalyzed by Sustainable and Recyclable Fe/ppm Pd Nanoparticles in Water at Room Temperature
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As a result of a unique synergy between ligand-free Fe/ppm Pd nanoparticles and PEG-containing designer surfactants, a facile and selective reduction of nitro-containing aromatics and heteroaromatics can be effected in water at room temperature in the presence of NaBH4. This new nanotechnology involves low catalyst loadings, is highly chemoselective, and tolerates a wide variety of functional groups. The process, which includes recycling of the entire aqueous medium, offers a general, environmentally responsible, and notably safe approach to highly valued reductions of nitro-containing compounds.
- Feng, Jie,Handa, Sachin,Gallou, Fabrice,Lipshutz, Bruce H.
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Read Online
- Coolade. A Low-Foaming Surfactant for Organic Synthesis in Water
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Several types of reduction reactions in organic synthesis are performed under aqueous micellar-catalysis conditions (in water at ambient temperature), which produce a significant volume of foam owing to the combination of the surfactant and the presence of gas evolution. The newly engineered surfactant “Coolade” minimizes this important technical issue owing to its low-foaming properties. Coolade is the latest in a series of designer surfactants specifically tailored to enable organic synthesis in water. This study reports the synthesis of this new surfactant along with its applications to gas-involving reactions.
- Lee, Nicholas R.,Cortes-Clerget, Margery,Wood, Alex B.,Lippincott, Daniel J.,Pang, Haobo,Moghadam, Farbod A.,Gallou, Fabrice,Lipshutz, Bruce H.
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p. 3159 - 3165
(2019/04/26)
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- Synergistic effects in Fe nanoparticles doped with ppm levels of (Pd + Ni). A new catalyst for sustainable nitro group reductions
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A remarkable synergistic effect has been uncovered between ppm levels of Pd and Ni embedded within iron nanoparticles that leads to mild and selective catalytic reductions of nitro-containing aromatics and heteroaromatics in water at room temperature. NaBH4 serves as the source of inexpensive hydride. Broad substrate scope is documented, along with several other features including: low catalyst loading, low residual metal in the products, and recycling of the catalyst and reaction medium, highlight the green nature of this new technology.
- Pang, Haobo,Gallou, Fabrice,Sohn, Hyuntae,Camacho-Bunquin, Jeffrey,Delferro, Massimiliano,Lipshutz, Bruce H.
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supporting information
p. 130 - 135
(2018/01/12)
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- Carbonyl Iron Powder: A Reagent for Nitro Group Reductions under Aqueous Micellar Catalysis Conditions
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An especially mild, safe, efficient, and environmentally responsible reduction of aromatic and heteroaromatic nitro-group-containing educts is reported that utilizes very inexpensive carbonyl iron powder (CIP), a highly active commercial grade of iron powder. These reductions are conducted in the presence of nanomicelles composed of TPGS-750-M in water, a recyclable aqueous micellar reaction medium. This new technology also shows broad scope and scalability and presents opportunities for multistep one-pot sequences involving this reducing agent.
- Lee, Nicholas R.,Bikovtseva, Agata A.,Cortes-Clerget, Margery,Gallou, Fabrice,Lipshutz, Bruce H.
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supporting information
p. 6518 - 6521
(2017/12/26)
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- FE NANOPARTICLES WITH PPM CONTENTS OF PD, CU AND/OR NI, REACTIONS IN WATER CATALYZED BY THEM
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The present application discloses a nanoparticle composition prepared from a mixture comprising: a) a transition metal salt; b) an iron salt; and c) a reducing agent; and methods for the use of such compositions, including the reduction of an organic compound comprising a nitro group to form an organic compound comprising an amine group, the Cu-catalyzed cyclization of an azide and an alkyne (click chemistry) and cross coupling reactions, notably Suzuki-Miyaura reactions. The transition metal salts are in particular Pd, Cu and Ni salts, the content of these metals being typically in the ppm range based on the major constituent Fe in the final products.
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Paragraph 0084; 0090
(2017/07/14)
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- Site-Selective Copper-Catalyzed Amination and Azidation of Arenes and Heteroarenes via Deprotonative Zincation
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Arene amination is achieved by site-selective C-H zincation followed by copper-catalyzed coupling with O-benzoylhydroxylamines under mild conditions. Key to this success is ortho-zincation mediated by lithium amidodiethylzincate base that is effective for a wide range of arenes, including nonactivated arenes bearing simple functionalities such as fluoride, chloride, ester, amide, ether, nitrile, and trifluoromethyl groups as well as heteroarenes including indole, thiophene, pyridine, and isoquinoline. An analogous C-H azidation is also accomplished using azidoiodinane for direct introduction of a useful azide group onto a broad scope of arenes and heteroarenes. These new transformations offer rapid access to valuable and diverse chemical space of aminoarenes. Their broad applications in organic synthesis and drug discovery are demonstrated in the synthesis of novel analogues of natural product (-)-nicotine and antidepressant sertraline by late-stage amination and azidation reactions.
- Hendrick, Charles E.,Bitting, Katie J.,Cho, Seoyoung,Wang, Qiu
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supporting information
p. 11622 - 11628
(2017/08/30)
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- Direct Hydroxylation and Amination of Arenes via Deprotonative Cupration
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Deprotonative directed ortho cupration of aromatic/heteroaromatic C-H bond and subsequent oxidation with t-BuOOH furnished functionalized phenols in high yields with high regio- and chemoselectivity. DFT calculations revealed that this hydroxylation reaction proceeds via a copper (I → III → I) redox mechanism. Application of this reaction to aromatic C-H amination using BnONH2 efficiently afforded the corresponding primary anilines. These reactions show broad scope and good functional group compatibility. Catalytic versions of these transformations are also demonstrated.
- Tezuka, Noriyuki,Shimojo, Kohei,Hirano, Keiichi,Komagawa, Shinsuke,Yoshida, Kengo,Wang, Chao,Miyamoto, Kazunori,Saito, Tatsuo,Takita, Ryo,Uchiyama, Masanobu
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p. 9166 - 9171
(2016/08/05)
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- Chemoselective reductions of nitroaromatics in water at room temperature
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A robust and green protocol for the reduction of functionalized nitroarenes to the corresponding primary amines has been developed. It relies on inexpensive zinc dust in water containing nanomicelles derived from the commercially available designer surfactant TPGS-750-M. This mild process takes place at room temperature and tolerates a wide range of functionalities. Highly selective reductions can also be achieved in the presence of common protecting groups.
- Kelly, Sean M.,Lipshutz, Bruce H.
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supporting information
p. 98 - 101
(2014/01/23)
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- Beyond directed ortho metalation: Ruthenium-catalyzed amide-directed C Ar-N activation/C-C coupling reaction of anthranilamides with organoboronates
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A new, catalytic, and general methodology for the synthesis of biaryls and heterobiaryls by the cross coupling of anthranilamide derivatives (o-NMe 2 benzamides) with aryl boroneopentylates is described. The reaction proceeds under catalytic RuH2(CO)(PPh3)3 conditions driven by the activation of the unreactive C-N bond by amide directing group (DG)-Ru catalyst chelation. High regioselectivity, orthogonality with the Suzuki-Miyaura reaction, operational simplicity, and convenient scale-up are features of these reactions which may lend themselves to industrial applications.
- Zhao, Yigang,Snieckus, Victor
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supporting information
p. 3200 - 3203
(2014/07/08)
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- Helix persistence and breakdown in oligoureas of metaphenylenediamine: Apparent diastereotopicity as a spectroscopic marker of helix length in solution
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Oligomeric ureas derived from m-phenylenediamine with chain lengths of up to seven urea linkages were made by iterative synthetic pathways. Three families were synthesized: 4 and 20, bearing a terminal chiral sulfinyl group; 24, bearing a terminal rotatio
- Clayden, Jonathan,Lemiegre, Loic,Morris, Gareth A.,Pickworth, Mark,Snape, Timothy J.,Jones, Lyn H.
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supporting information; experimental part
p. 15193 - 15202
(2009/03/12)
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- Achieving conformational control over C-C, C-N and C-O bonds in biaryls, N,N′-diarylureas and diaryl ethers: Advantages of a relay axis
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The orientation of Ar-C, Ar-N and Ar-O bonds in biaryls, N,N′-diarylureas and diaryl ethers (whose conformers are distinguishable by NMR) may be controlled with a selectivity up to >95: 5 by an adjacent stereogenic centre; the selectivity may be greater when a second stereogenic axis is inserted between the controlling centre and the slowly rotating bond. The Royal Society of Chemistry.
- Betson, Mark S.,Bracegirdle, Ann,Clayden, Jonathan,Helliwell, Madeleine,Lund, Andrew,Pickworth, Mark,Snape, Timothy J.,Worrall, Christopher P.
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p. 754 - 756
(2007/10/03)
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- Trapping of translocated radicals by tetrathiafulvalene radical cation
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Aryl radicals are generated by electron transfer from tetrathiafulvalene to arenediazonium salts.The aryl radicals are translocated into alkyl radicals which undergo a C-S or C-C bond formation to tetrathiafulvalene radical cation, depending on the nucleophilicity/electrophilicity of the translocated carbon radical.
- Murphy, John A.,Roome, Stephen J.
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p. 1349 - 1358
(2007/10/02)
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- The Geometry of Displacements at Nonstereogenic Atoms: The Formal Displacement of Alkoxide from Alkoxyamines by Organolithium Reagents
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Amination of organolithium regents can be achieved by reaction with methyllithium-alkoxyamines.Details of the methodology and analysis of the reaction mechanism are presented.Reactions of methyl-, ethyl-, n-butyl-, sec-butyl-, tert-butyl-, phenyl-, and (o-methoxyphenyl)lithium with methyllithium-methoxyamine give the corresponding amines, isolated as the benzamides, in yields of 71-97percent.Lower yields are obtained with o-lithio-N,N-diisopropylbenzamide, 4-lithiodibenzothiophene, n-butylmagnesium bromide, and phenylmagnesium bromide.Reactions of n-butyl, sec-butyl-, tert-butyl-, and phenyllithium with methyllithium-N-methylmethoxyamine provide the corresponding N-methyl-amines, isolated as the benzamides, in yields of 30-70percent.Retention of the N-methyl group in these reactions is considered to rule out a nitrene intermediate.Involvement of a lithium alkoxyamide is suggested by the formation and substitution of that species by two different routes.Dilithiation of N-methoxy-N-amine (17) gives, after an intramolecular reaction and addition of acetyl chloride, N-acetylindoline, in 78percent yield.Dilithiation of N-methyl-N-amine (19) gives N-methyl-N-acetamide (20), after rection with acetyl chloride.The nitrogen transfer in this conversion is shown by a double labeling experiment to be intermolecular.This results is taken to suggest that the bond angles required for displacement cannot be achieved in a six-membered ring, and the mechanism of the reaction involves a complex in which displacement occurs via an SN2-like transition state.The exocyclic-endocyclic intramolecular-intermolecular test is noted to provide a general approach for determination of the geomatry of reactions at nonstereogenic centers.
- Beak, Peter,Basha, Anwer,Kokko, Bruce,Loo, DeKai
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p. 6016 - 6023
(2007/10/02)
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