55980-45-5Relevant articles and documents
Exploiting Continuous Processing for Challenging Diazo Transfer and Telescoped Copper-Catalyzed Asymmetric Transformations
Crowley, Daniel C.,Brouder, Thomas A.,Kearney, Aoife M.,Lynch, Denis,Ford, Alan,Collins, Stuart G.,Maguire, Anita R.
, p. 13955 - 13982 (2021/09/02)
Generation and use of triflyl azide in flow enables efficient synthesis of a range of α-diazocarbonyl compounds, including α-diazoketones, α-diazoamides, and an α-diazosulfonyl ester, via both Regitz-type diazo transfer and deacylative/debenzoylative diazo-transfer processes with excellent yields and offers versatility in the solvent employed, in addition to addressing the hazards associated with handling of this highly reactive sulfonyl azide. Telescoping the generation of triflyl azide and diazo-transfer process with highly enantioselective copper-mediated intramolecular aromatic addition and C-H insertion processes demonstrates that the reaction stream containing the α-diazocarbonyl compound can be obtained in sufficient purity to pass directly over the immobilized copper bis(oxazoline) catalyst without detrimentally impacting the catalyst enantioselectivity.
Br?nsted Acid Catalyzed Dearomatization by Intramolecular Hydroalkoxylation/Claisen Rearrangement: Diastereo- and Enantioselective Synthesis of Spirolactams
Chen, Peng-Fei,Wang, Binju,Wu, Peng,Ye, Long-Wu,Zhou, Bo
supporting information, p. 27164 - 27170 (2021/11/22)
Described herein is a novel Br?nsted acid catalyzed intramolecular hydroalkoxylation/Claisen rearrangement, allowing the practical and atom-economic synthesis of a range of valuable spirolactams from readily available ynamides in generally good to excellent yields with excellent diastereoselectivities and broad substrate scope. Importantly, an unexpected dearomatization of nonactivated arenes and heteroaromatic compounds is involved in this tandem sequence. Moreover, an asymmetric version of this tandem cyclization was also achieved by efficient kinetic resolution by chiral phosphoric acid catalysis. In addition, the [3,3]-rearrangement is shown to be kinetically preferred over the related [1,3]-rearrangement by theoretical calculations.
Pathways of the reaction between N,N-disubstituted propargylic amines and cationic zirconium complexes
Dzhemilev, U. M.,Kadikova, R. N.,Ramazanov, I. R.,Saitova, Z. R.
, p. 61 - 67 (2020/04/21)
The reaction of N-tert-alkyl-substituted propargylic amines with trialkylalanes in the presence of 20 mol.% Cp2ZrCl2 was studied. The pattern of the products depended on the nature of substituents at the nitrogen atom. N-tert-Alkyl-N-arylmethyl-substituted propargylic amines when reacted in CH2Cl2 aff ord a mixture of N-tert-alkyl-N-(arylmethyl)alkylamines and N-tertalkyl-N-(arylmethyl)amines at ratios from {2: 3 to {3: 2 in total yield of 70–95%. In hexane, N-tert-alkyl-N-(arylmethyl)amines are produced selectively. N-Alkyl-N-tert-alkyl-substituted propargylic amines similar to N-isoalkyl-substituted ones underwent a Zr-promoted hydride transfer to aff ord (2E)-alkenylamines in good yield (58–69%).
