6941-24-8Relevant academic research and scientific papers
AMINE-BORANES AS BIFUNCTIONAL REAGENTS FOR DIRECT AMIDATION OF CARBOXYLIC ACIDS
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Paragraph 0008-0009; 0063-0064, (2022/03/04)
The present invention generally relates to a process for selective and direct activation and subsequent amidation of aliphatic and aromatic carboxylic acids to afford an amide R3CONR1R2. That the process is capable of delivering gaseous or low-boiling point amines provides a major advantage over existing methodologies, which involves an intermediate of triacyloxyborane-amine complex [(R3CO2)3—B—NHR1R2]. This procedure readily produces primary, secondary, and tertiary amides, and is compatible with the chirality of the acid and amine involved. The preparation of known pharmaceutical molecules and intermediates has also been demonstrated.
Weak base-promoted selective rearrangement of oxaziridines to amidesviavisible-light photoredox catalysis
Park, Jin,Park, Sehoon,Jang, Gwang Seok,Kim, Ran Hui,Jung, Jaehoon,Woo, Sang Kook
, p. 9995 - 9998 (2021/10/06)
The selective rearrangement of oxaziridines to amidesviaa single electron transfer (SET) pathway is unexplored. In this study, we present a weak base-promoted selective rearrangement of oxaziridines to amidesviavisible-light photoredox catalysis. The developed method shows excellent functional group tolerance with a broad substrate scope and good to excellent yields. Furthermore, control experiments and density functional theory (DFT) calculations are performed to gain insight into the reactivity and selectivity.
Mild and Selective Rhodium-Catalyzed Transfer Hydrogenation of Functionalized Arenes
Wang, Yuhan,Chang, Zhiqian,Hu, Yan,Lin, Xiao,Dou, Xiaowei
supporting information, p. 1910 - 1914 (2021/03/08)
Diboron-mediated rhodium-catalyzed transfer hydrogenation of functionalized arenes is reported. In addition to good functional group tolerance, the reaction features operational simplicity and controllable chemoselectivity. The general applicability of this procedure is demonstrated by the selective hydrogenation of a range of arenes, including functionalized benzenes, biphenyls, and polyaromatics.
Three-Component Visible-Light-Induced Palladium-Catalyzed 1,2-Alkyl Carbamoylation/Cyanation of Alkenes
Jia, Xiangqing,Zhang, Ziyan,Gevorgyan, Vladimir
, p. 13217 - 13222 (2021/11/01)
A mild visible-light-induced Pd-catalyzed one-pot three-component alkyl-carbamoylation and cyanation of alkenes was developed. This general transformation, which proceeds via the in situ formation of a reactive ketenimine intermediate, allows for a rapid construction of a broad range of valuable amides and nitriles from readily available alkenes, alkyl iodides, and isocyanides. An efficient synthesis of tetrazole and amidine via this approach was also demonstrated.
Amine-boranes as Dual-Purpose Reagents for Direct Amidation of Carboxylic Acids
Choudhary, Shivani,Hamann, Henry J.,Ramachandran, P. Veeraraghavan
supporting information, (2020/11/13)
Amine-boranes serve as dual-purpose reagents for direct amidation, activating aliphatic and aromatic carboxylic acids and, subsequently, delivering amines to provide the corresponding amides in up to 99% yields. Delivery of gaseous or low-boiling amines as their borane complexes provides a major advantage over existing methodologies. Utilizing amine-boranes containing borane incompatible functionalities allows for the preparation of functionalized amides. An intermolecular mechanism proceeding through a triacyloxyborane-amine complex is proposed.
A convenient synthesis of N-tert-butyl amides by the reaction of di-tert-butyl dicarbonate and nitriles catalyzed by Cu(OTf)2
Chen, Junqing,Feng, Chengliang,Ji, Min,Tang, Yuqi,Yang, Wanfeng
, p. 602 - 608 (2020/04/27)
The utility of Cu(OTf)2 as the catalyst for the synthesis of a series of N-tert-butyl amides in excellent isolated yields via the reaction of nitriles (alkyl, aryl, benzyl, and furyl nitriles) with di-tert-butyl dicarbonate is described. Cu(OTf)2 is a highly stable and efficient catalyst for the present Ritter reaction under solvent-free conditions at room temperature.
Nickel-Catalyzed Multicomponent Coupling Reaction of Alkyl Halides, Isocyanides and H2O: An Expedient Way to Access Alkyl Amides
Li, Qiao,Jin, Hongwei,Liu, Yunkui,Zhou, Bingwei
supporting information, p. 3466 - 3472 (2020/09/15)
We herein describe a Ni-catalyzed multicomponent coupling reaction of alkyl halides, isocyanides, and H2O to access alkyl amides. Bench-stable NiCl2(dppp) is competent to initiate this transformation under mild reaction conditions, thus allowing easy operation and adding practical value. Substrate scope studies revealed a broad functional group tolerance and generality of primary and secondary alkyl halides in this protocol. A plausible catalytic cycle via a SET process is proposed based on preliminary experiments and previous literature.
Reductive amidation of alkyl tosylates with isocyanates by a Ni/Co-dual catalytic system
Michiyuki, Takuya,Osaka, Itaru,Komeyama, Kimihiro
supporting information, p. 1247 - 1250 (2020/02/04)
Reductive amidation of alkyl tosylates with isocyanates using the Ni/Co-dual catalytic system is disclosed. The method proceeds efficiently under mild conditions, giving rise to the corresponding alkyl amides. Notably, the protocol can discriminate the steric environment of two alkyl tosylate moieties, enabling regioselective mono-amidation at the less-bulky site.
Nickel/Photoredox-Catalyzed Amidation via Alkylsilicates and Isocyanates
Zheng, Shuai,Primer, David N.,Molander, Gary A.
, p. 7957 - 7961 (2017/11/10)
A nickel/photoredox, dual-catalyzed amidation reaction between alkylsilicate reagents and alkyl/aryl isocyanates is reported. In contrast to the previously reported reductive coupling process, this protocol is characterized by mild reaction conditions and the absence of a stoichiometric reductant. A mechanistic hypothesis involving a nickel-isocyanate adduct is proposed based on literature precedent and further validation by experimental results.
Nickel-Catalyzed Reductive Amidation of Unactivated Alkyl Bromides
Serrano, Eloisa,Martin, Ruben
supporting information, p. 11207 - 11211 (2016/10/13)
A user-friendly, nickel-catalyzed reductive amidation of unactivated primary, secondary, and tertiary alkyl bromides with isocyanates is described. This catalytic strategy offers an efficient synthesis of a wide range of aliphatic amides under mild conditions and with an excellent chemoselectivity profile while avoiding the use of stoichiometric and sensitive organometallic reagents.
