123387-50-8Relevant articles and documents
Generation and Alkylation of α-Carbamyl Radicals via Organic Photoredox Catalysis
McManus, Joshua B.,Onuska, Nicholas P. R.,Nicewicz, David A.
, p. 9056 - 9060 (2018)
Strategies for the direct C-H functionalization of amines are valuable as these compounds comprise a number of pharmaceuticals, agrochemicals and natural products. This work describes a novel method for the C-H functionalization of carbamate-protected secondary amines via α-carbamyl radicals generated using photoredox catalysis. The use of the highly oxidizing, organic acridinium photoredox catalyst allows for direct oxidation of carbamate-protected amines with high redox potentials to give the corresponding carbamyl cation radical. Following deprotonation, the resultant open-shell species can be intercepted by a variety of Michael acceptors to give elaborate α-functionalized secondary amines. The reaction proceeds under mild conditions without the requirement of exogenous redox mediators or substrate prefunctionalization. Additionally, we were able to showcase the utility of this methodology through the enantioselective synthesis of the indolizidine alkaloid, (+)-monomorine I.
Single-step conversion of N-benzyl, N-trityl and N-diphenylmethyl amines to t-butyl carbamates using polymethylhydrosiloxane
Chandrasekhar,Babu, B. Nagendra,Reddy, Ch. Raji
, p. 2057 - 2059 (2003)
t-Butyl carbamates were obtained efficiently in high yields from the corresponding N-benzyl, N-trityl and N-diphenylmethyl precursors in a single-step reductive transformation employing polymethylhydrosiloxane and di-t-butyl dicarbonate under Pd(OH)2/C catalysis.
Deaminative Reductive Methylation of Alkylpyridinium Salts
Bercher, Olivia P.,Plunkett, Shane,Mortimer, Thomas E.,Watson, Mary P.
supporting information, p. 7059 - 7063 (2021/09/18)
Methyl groups can imbue valuable properties in organic molecules, often leading to enhanced bioactivity. To enable efficient installation of methyl groups on simple building blocks and in late-stage functionalization, a nickel-catalyzed reductive coupling of secondary Katritzky alkylpyridinium salts with methyl iodide was developed. When coupled with formation of the pyridinium salt from an alkyl amine, this method allows amino groups to be readily transformed to methyl groups with broad functional group and heterocycle tolerance.
Amine-Responsive Disassembly of AuI–CuI Double Salts for Oxidative Carbonylation
Cao, Yanwei,Yang, Jian-Gong,Deng, Yi,Wang, Shengchun,Liu, Qi,Shen, Chaoren,Lu, Wei,Che, Chi-Ming,Chen, Yong,He, Lin
supporting information, p. 2080 - 2084 (2019/12/24)
A sensitive amine-responsive disassembly of self-assembled AuI-CuI double salts was observed and its utilization for the synergistic catalysis was enlightened. Investigation of the disassembly of [Au(NHC)2][CuI2] revealed the contribution of Cu-assisted ligand exchange of N-heterocyclic carbene (NHC) by amine in [Au(NHC)2]+ and the capacity of [CuI2]? on the oxidative step. By integrating the implicative information coded in the responsive behavior and inherent catalytic functions of d10 metal complexes, a catalyst for the oxidative carbonylation of amines was developed. The advantages of this method were clearly reflected on mild reaction conditions and the significantly expanded scope (51 examples); both primary and steric secondary amines can be employed as substrates. The cooperative reactivity from Au and Cu centers, as an indispensable prerequisite for the excellent catalytic performance, was validated in the synthesis of (un)symmetric ureas and carbamates.
