94535-33-8Relevant articles and documents
Direct access to α-sulfenylated amides/esters: Via sequential oxidative sulfenylation and C-C bond cleavage of 3-oxobutyric amides/esters
Jiang, Yi,Deng, Jie-Dan,Wang, Hui-Hong,Zou, Jiao-Xia,Wang, Yong-Qiang,Chen, Jin-Hong,Zhu, Long-Qing,Zhang, Hong-Hua,Peng, Xue,Wang, Zhen
supporting information, p. 802 - 805 (2018/02/06)
An efficient, environmentally benign and unprecedented synthesis of various α-sulfenylated amides/esters has been developed under oxygen atmosphere. The reaction shows good functional group tolerance and excellent chemo/regioselectivity. All the desired products were obtained in moderate to excellent yields, even on the gram scale. Practically, the related α-thiol Weinreb amide can be readily transferred to a series of prospective compounds, and selenium atom can be introduced to the α-sites of the amides in high yields.
Intermolecular carbene S-H insertion catalysed by engineered myoglobin-based catalysts
Tyagi, Vikas,Bonn, Rachel B.,Fasan, Rudi
, p. 2488 - 2494 (2015/03/30)
The first example of a biocatalytic strategy for the synthesis of thioethers via an intermolecular carbene S-H insertion reaction is reported. Engineered variants of sperm whale myoglobin were found to efficiently catalyze this C-S bond forming transformation across a diverse set of aryl and alkyl mercaptan substrates and α-diazoester carbene donors, providing high conversions (60-99%) and high numbers of catalytic turnovers (1100-5400). Furthermore, the enantioselectivity of these biocatalysts could be tuned through mutation of amino acid residues within the distal pocket of the hemoprotein, leading to myoglobin variants capable of supporting asymmetric S-H insertions with up to 49% ee. Rearrangement experiments support a mechanism involving the formation of a sulfonium ylide generated upon attack of the thiol substrate to a heme-bound carbene intermediate. This journal is
Iron(III) corroles and porphyrins as superior catalysts for the reactions of diazoacetates with nitrogen- or sulfur-containing nucleophilic substrates: Synthetic uses and mechanistic insights
Aviv, Iris,Gross, Zeev
scheme or table, p. 3995 - 4005 (2009/05/26)
A thorough mechanistic investigation has been performed on the reactions of primary and secondary amines with diazoacetates, which proceed uniquely quickly and efficiently when catalyzed by iron(III) corroles and porphyrins. Two major differences in relation to other metal-based catalysts are that the iron complexes are not poisoned by excess amine and that metal-carbene intermediates are apparently not involved in the reaction pathway. The results instead point towards nitrogen ylide intermediates formed by nucleophilic attack of the amines on diazoacetate-coordinated iron complexes. Nitrogen ylides are also formed when allyl- and propargylsubstituted tertiary amines react with diazoacetates, a scenario that smoothly leads to 2,3-rearrangement reaction products with catalytic amounts of the iron(III) complexes. Similar findings regarding the superiority of the iron-(III) complexes (in terms of catalyst loading, chemical yields, and reaction conditions) were obtained with thiols (S-H insertion) and sulfides (2,3-rear-rangement reactions), which suggest similar mechanisms operate in these cases.
