Synthesen von 2,3-Dioxoalkylphosphonaten und anderer neuartiger ?-Ketophosphonate sowie eines Phosphinopyruvamids ( = (Alkyloxyphosphinyl)pyruvamids)
作者:Richard Neidlein、Helmut Feistauer
DOI:10.1002/hlca.19960790329
日期:1996.5.8
Syntheses of 2,3-Dioxoalkylphonates and Other Novel β-Ketophosphonates As Well As of a Phosphinopyruvamide ( = (Alkyloxyphosphinyl)pyruvamide)
2,3-二氧代烷基膦酸酯和其他新型β-酮膦酸酯以及膦酰丙酮酰胺(=(烷氧基膦基)丙酮酰胺)的合成
1- and 2-Azetines via Visible Light-Mediated [2 + 2]-Cycloadditions of Alkynes and Oximes
作者:Emily R. Wearing、Dominique E. Blackmun、Marc R. Becker、Corinna S. Schindler
DOI:10.1021/jacs.1c07523
日期:2021.10.6
accessible upon intermolecular [2 + 2]-cycloaddition via triplet energy transfer from a commercially available iridium photocatalyst, the selective formation of 1-azetines proceeds upon a second, consecutive, energy transfer process. Mechanistic studies are consistent with a stepwise reactionmechanism via N–O bond homolysis following the second energy transfer event to result in the formation of 1-azetine products
Synthesis and antimicrobial properties of cephalosporin derivatives substituted on the C(7) nitrogen with arylmethyloxyimino or arylmethyloxyamino alkanoyl groups
7-aminocephalosporanic acid (7-ACA) derivatives substituted on the C(7) nitrogen with 2-(arylmethyloxyimino)propionyl (3a-f), 2-(arylmethyloxyamino)propionyl (4a-d) and (arylmethyloxyamino)acetyl (2a-d) moieties were synthesized by reaction of the appropriate acylating agents with 7-ACA protected as a t-butyl ester, followed by removal of the t-butyl protecting group. The new compounds, tested in vitro for their antimicrobial
Synthesis of azetidines via visible-light-mediated intermolecular [2+2] photocycloadditions
作者:Marc R. Becker、Emily R. Wearing、Corinna S. Schindler
DOI:10.1038/s41557-020-0541-1
日期:2020.10
Intermolecular [2+2] photocycloadditions represent a powerful method for the synthesis of highly strained, four-membered rings. Although this approach is commonly employed for the synthesis of oxetanes and cyclobutanes, the synthesis of azetidines via intermolecular aza Paternò–Büchi reactions remains highly underdeveloped. Here we report a visible-light-mediated intermolecular aza Paternò–Büchi reaction
Enantioselective allylation of α-ketoester oximes with an external chiral ligand: Asymmetric synthesis of allylglycines and allylalanine
作者:Stephen Hanessian、Rui-Yang Yang
DOI:10.1016/s0040-4039(96)02112-0
日期:1996.12
A highly enantioselective allylation of oximes of alpha-ketoesters is described with phenyl substituted chiral bis(oxazoline) as external ligand of allylzinc reagents. This method provides an efficient and convenient access to N-benzyloxy allylglycine, allylglycine and chain substituted variants with high enantiomeric purities. Copyright (C) 1996 Elsevier Science Ltd