Tribromogermyl monochelates — derivatives of N,N-disubstituted 2-hydroxycarboxylic amides

Abstract

Reactions of GeBr 4 with N,N dimethyl 2 trimethylsiloxypropionamide (2a), (S) 2 trime thylsiloxypropionpyrrolidide ((S) 2b), and N,N dimethyl O (trimethylsilyl)mandelamide (2c) afforded pentacoordinated neutral (O,O) monochelates, viz., N,N dimethyl 2 tribromoger myloxypropionamide (3a), (S) 2 tribromogermyloxypropionpyrrolidide ((S) 3b), and N,N di methyl O (tribromogermyl)mandelamide (3c), respectively. X ray diffraction study was per formed for tribromides 3a, (S) 3b, and 3c, as well as for the N,N dimethylmandelamide (1c) described earlier. According to the X ray diffraction data, the Ge atom in tribromides 3a, (S) 3b, and 3c is pentacoordinated and has trigonal bipyramidal configuration with two halo gen atoms and oxygen atom of the ether group in the equatorial positions and the halogen atom and the amide oxygen atom in the axial fragment, the bonds in which are somewhat longer as compared to the analogous bonds in tetracoordinated Ge compounds.

Cross-benzoin and Stetter-type reactions mediated by KOtBu-DMF via an electron-transfer process

“…The reaction mixture was stirred for 5 h at -70 °C, then allowed to reach room temperature and quenched with saturated aqueous NH 4 Cl solution (2.5 mL). The organic phase was separated, dried (Na 2 SO 4 ), concentrated, and eluted from a column of silica gel with 3.5:1 cyclohexane-AcOEt to separate apolar compounds, and then with 10:1 AcOEt-MeOH to afford 6 36…”

Cefonicid Benzathine Salt: A Convenient, Lean, and High-Performance Protocol to Make an Old Cephalosporin Shine

“…Both 5-phenyl-1,3-dioxolane-4-one (DOX) and alkyl-DOX are part of this group, and their simple, synthetic accessibility has been proven by the fact that fewer toxic resources were used as ring-closing agents for mandelic acid ( 1 ) in acetone or cyclohexane, giving good isolated yields. Having observed this new frontier of compounds, we have investigated the possibility of replacing phosgene-derived OCA with DOX, which was obtained from paraformaldehyde, and with methyl- and ethyl-DOX, which were synthetized from trimethyl and triethyl orthoformate (TMOF and TEOF) [ 45 , 46 , 47 , 48 , 49 , 50 ], as illustrated in Figure 3 .…”