13492-59-6Relevant articles and documents
Carbamates: A Directing Group for Selective C-H Amidation and Alkylation under Cp*Co(III) Catalysis
Bera, Sourav Sekhar,Maji, Modhu Sudan
supporting information, p. 2615 - 2620 (2020/04/08)
The selective reactivity of carbamate and thiocarbamate toward alkylation and amidation is reported under stable, high-valent, cost-effective cobalt(III) catalysis. This method reveals the wide possibility of designing a different branch of synthetically
Palladium-catalyzed intramolecular oxidative C-H sulfuration of aryl thiocarbamates
Zhao, Yingwei,Xie, Yinjun,Xia, Chungu,Huang, Hanmin
supporting information, p. 2471 - 2476 (2014/09/17)
A palladium-catalyzed intramolecular C-H bond sulfuration reaction of aryl thiocarbamates has been developed. This strategy provides a new route to benzo[d][1,3]oxathiol-2-ones with tolerance of a wide range of substituents. Mechanistic studies suggested
Highly chemoselective methylation and esterification reactions with dimethyl carbonate in the presence of NaY faujasite. The case of mercaptophenols, mercaptobenzoic acids, and carboxylic acids bearing OH substituents
Selva, Maurizio,Tundo, Pietro
, p. 1464 - 1470 (2007/10/03)
In the presence of NaY faujasite, the reactions of dimethyl carbonate (DMC) with several ambident nucleophiles such as o- and p-mercaptophenols (1a,b), o- and p-mercaptobenzoic acids (2a,b), o- and p-hydroxybenzoic acids (3a,b), mandelic and phenyllactic acids (4, 5), have been explored under batch conditions. Highly chemoselective reactions can be performed: at 150 °C, compounds 1 and 2 undergo only a S-methylation reaction, without affecting OH and CO2H groups; at 165 °C, acids 3-5 form the corresponding methyl esters, while both their aromatic and aliphatic OH substituents are fully preserved from methylation and/or transesterification processes. Typical selectivities are of 90-98% and isolated yields of products (S-methyl derivatives and methyl esters, respectively) are in the range of 85-96%. A comparative study with K2CO3 as a catalyst is also reported. Although the base (K2CO3) turns out to be more active than the zeolite, the chemoselectivity is elusive: compounds 2a,b undergo simultaneous S-methylation and esterification reactions, and acids 3-5 yield complex mixtures of products of O-methylation, O-methoxycarbonylation, and esterification of their OH and CO2H groups, respectively. Overall, the combined use of a nontoxic reagent/solvent (DMC) and a safe promoter (NaY) imparts a genuine ecofriendly nature to the investigated synthesis.
