26819-08-9Relevant academic research and scientific papers
Deoxygenative hydroboration of primary, secondary, and tertiary amides: Catalyst-free synthesis of various substituted amines
Yi, Jaeeun,Kim, Hyun Tae,Jaladi, Ashok Kumar,An, Duk Keun
supporting information, p. 129 - 132 (2021/11/17)
Transformation of relatively less reactive functional groups under catalyst-free conditions is an interesting aspect and requires a typical protocol. Herein, we report the synthesis of various primary, secondary, and tertiary amines through hydroboration of amides using pinacolborane under catalyst-free and solvent-free conditions. The deoxygenative hydroboration of primary and secondary amides proceeded with excellent conversions. The comparatively less reactive tertiary amides were also converted to the corresponding N,N-diamines in moderate yields under catalyst-free conditions, although alcohols were obtained as a minor product.
Generation of alkyl radicals from alkylsilyl peroxides and their applications to C-N or C-O bond formations
Sakurai, Shunya,Kato, Terumasa,Sakamoto, Ryu,Maruoka, Keiji
, p. 172 - 179 (2018/12/11)
This article describes a novel method for the generation of alkyl radicals from alkylsilyl peroxides and their applications to the Cu-catalyzed mono-N-alkylation of amides or arylamines, and to the O-alkylation of carboxylic acids. The use of alkylsilyl peroxides as alkyl radical sources includes the following synthetic advantages: i) various alkylsilyl peroxides can be readily synthesized from the corresponding alcohols and be stored at bench, and ii) a variety of alkyl radicals can be generated efficiently under mild conditions.
Bis(trialkylsilyl) peroxides as alkylating agents in the copper-catalyzed selective mono-: N -alkylation of primary amides
Sakamoto, Ryu,Sakurai, Shunya,Maruoka, Keiji
supporting information, p. 6484 - 6487 (2017/07/10)
The copper-catalyzed selective mono-N-alkylation of primary amides with bis(trialkylsilyl) peroxides as alkylating agents was reported. The results of a mechanistic study suggest that this reaction should proceed via a free radical process that includes the generation of alkyl radicals from bis(trialkylsilyl) peroxides.
Alkylsilyl Peroxides as Alkylating Agents in the Copper-Catalyzed Selective Mono-N-Alkylation of Primary Amides and Arylamines
Sakamoto, Ryu,Sakurai, Shunya,Maruoka, Keiji
supporting information, p. 9030 - 9033 (2017/07/11)
The copper-catalyzed selective mono-N-alkylation of primary amides or arylamines using alkylsilyl peroxides as alkylating agents is reported. The reaction proceeds under mild reaction conditions and exhibits a broad substrate scope with respect to the alkylsilyl peroxides, as well as to the primary amides and arylamines. Mechanistic studies suggest that the present reaction should proceed through a free-radical process that includes alkyl radicals generated from the alkylsilyl peroxides.
Metal-Free Synthesis of Dibenzoxazepinones via a One-Pot SNAr and Smiles Rearrangement Process: Orthogonality with Copper-Catalyzed Cyclizations
Hurst, Timothy E.,Kitching, Matthew O.,Da Frota, Lívia C. R. M.,Guimar?es, Keller G.,Dalziel, Michael E.,Snieckus, Victor
, p. 1455 - 1460 (2015/06/30)
Reported is the transition-metal-free synthesis of substituted dibenzoxazepinones using a convergent domino SNAr-Smiles rearrangement-SNAr process. Substrate-scope investigations demonstrated the critical importance of ring electroni
A mild, copper-catalysed amide deprotection strategy: Use of tert-butyl as a protecting group
Evans, Vikki,Mahon, Mary F.,Webster, Ruth L.
supporting information, p. 7593 - 7597 (2014/12/10)
Mild methods for the deprotection of organic substrates are of fundamental importance in synthetic chemistry. A new room temperature method using a catalytic amount of Cu(OTf)2is reported. This allows use of the tert-butyl group as an amide protecting group. The methodology is also extended to Boc-deprotection.
The α-effect in hydrazinolysis of 4-chloro-2-nitrophenyl x-substituted-benzoates: Effect of substituent x on reaction mechanism and the α-effect
Kim, Min-Young,Kim, Tae-Eun,Lee, Jieun,Um, Ik-Hwan
, p. 2271 - 2276 (2014/09/29)
Second-order rate constants (kN) have been measured spectrophotometrically for the reaction of 4-chloro-2- nitrophenyl X-substituted-benzoates (6a-6h) with a series of primary amines including hydrazine in 80 mol % H2O/20 mol % DMSO at 25.0°C. The Bronsted-type plot for the reaction of 4-chloro-2-nitrophenyl benzoate (6d) is linear with βnuc = 0.74 when hydrazine is excluded from the correlation. Such a linear Bronsted-type plot is typical for reactions reported previously to proceed through a stepwise mechanism in which expulsion of the leaving group occurs in the rate-determining step (RDS). The Hammett plots for the reactions of 6a-6h with hydrazine and glycylglycine are nonlinear. In contrast, the Yukawa-Tsuno plots exhibit excellent linear correlations with ?X = 1.29-1.45 and r = 0.53-0.56, indicating that the nonlinear Hammett plots are not due to a change in RDS but are caused by resonance stabilization of the substrates possessing an electron-donating group (EDG). Hydrazine is ca. 47-93 times more reactive than similarly basic glycylglycine toward 6a-6h (e.g., the α-effect). The α-effect increases as the substituent X in the benzoyl moiety becomes a stronger electronwithdrawing group (EWG), indicating that destabilization of the ground state (GS) of hydrazine through the repulsion between the nonbonding electron pairs on the two N atoms is not solely responsible for the substituent-dependent α-effect. Stabilization of transition state (TS) through five-membered cyclic TSs, which would increase the electrophilicity of the reaction center or the nucleofugality of the leaving group, contributes to the α-effect observed in this study.
Copper-catalyzed cross-coupling interrupted by an opportunistic smiles rearrangement: An efficient domino approach to dibenzoxazepinones
Kitching, Matthew O.,Hurst, Timothy E.,Snieckus, Victor
, p. 2925 - 2929 (2012/05/04)
Unexpected Smiles! An unusual and highly regioselective synthesis of dibenzoxazepinones by a domino sequence assisted by an unexpected Smiles rearrangement is reported. The process is effective on electronically differentiated phenols and shows a high tolerance to variation in the benzamide substituents. A plausible path for the reaction, supported by preliminary mechanistic data, is offered. Copyright
The conversion of aryl and heteroaryl methylketones to the corresponding secondary or tertiary amides
Ding, Jiaoyang,Cao, Liping,Wang, Jungang,Xue, Weijian,Zhu, Yanping,Wu, Anxin
experimental part, p. 298 - 301 (2011/10/02)
Secondary or tertiary amides have been prepared directly from aryl, heteroaryl methyl ketones using an iodineamine-NaOH system which afforded the expected products in good yields in an aqueous medium. The present method has the advantages of using inexpensive reagents, mild reaction condition and ease of manipulation.
Practical access to amines by platinum-catalyzed reduction of carboxamides with hydrosilanes: Synergy of dual Si-H groups leads to high efficiency and selectivity
Hanada, Shiori,Tsutsumi, Emi,Motoyama, Yukihiro,Nagashima, Hideo
supporting information; experimental part, p. 15032 - 15040 (2010/01/29)
The synergetic effect of two Si-H groups leads to efficient reduction of carboxamides to amines by platinum catalysts under mild conditions. The rate of the reaction is dependent on the distance of two Si-H groups; 1,1,3,3-tetramethyldisiloxane (TMDS) and 1,2-bis(dimethylsilyl)benzene are found to be an effective reducing reagent. The reduction of amides having other reducible functional groups such as NO2, CO2R, CN, CdC, Cl, and Br moieties proceeds with these groups remaining intact, providing a reliable method for the access to functionalized amine derivatives. The platinum-catalyzed reduction of amides with polymethylhydrosiloxane (PMHS) also proceeds under mild conditions. The reaction is accompanied by automatic removal of both platinum and silicon wastes as insoluble silicone resin, and the product is obtained by simple extraction. A mechanism involving double oxidative addition of TMDS to a platinum center is discussed.
