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Ryszard Andruszkiewicz Ewa Liedke-Przybysz 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):2274-2278
Abstract Reaction of succinimide with diphenylchlorophosphate in the presence of lithium bis(trimethylsilyl)amide followed by aqueous work-up led to the formation of amidophosphate 3. The same reaction performed in the presence of sodium hydride yield N-(diphenylphosphoryl)succinimde 4, which undergoes nucleophilic ring opening with sodium alkoxides resulted in the formation of phosphoroamidate analogues 5 a-d in good yields. GRAPHICAL ABSTRACT 相似文献
75.
Xiao-Bo Ma Jing-Lin Zhang 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):233-237
Abstract 1,3,2-Diazaphosphetidin-4-one derivatives were synthesized. Their 1H NMR signals at ambient temperature displaed a broad doublet which eventually coalesced before becoming sharp upon warming, and the 13C NMR spectra also showed that the α-and β-carbons of the dialkylamino group were non-equivalent. The phenomena were ascribed to restricted rotation about the exocyclic P—N bond. 相似文献
76.
Abstract The mass spectrometric behavior of 1-(N-benzyloxycarbonylamino)arylmethyl-phosphonate phenyl monoesters was investigated under positive ion electrospray ionization conditions. All nitrogen-protonated title compounds undergo four- and/or six-membered ring rearrangements to yield nitrogen-containing fragment ions by consecutive or simultaneous loss of a carbon dioxide and phenyl hydrogen phosphonate or phenyl benzylphosphonate or an arylmethylimine. All oxygen-protonated title compounds undergo four- to six-membered ring rearrangements to produce fragment ions by loss of a carbon dioxide plus an arylmethylimine, or phenyl benzylphosphonate, by consecutive or simultaneous loss of benzyl phenyl ether and isocyanic acid. The fragmentation is obviously different from the corresponding methyl and ethyl monoesters, which show a tendency to undergo intramolecular four-membered ring rearrangements only. GRAPHICAL ABSTRACT 相似文献
77.
A variety of aldehyde N,N-dimethylhydrazones are rapidly converted into the corresponding nitriles using oxone supported on wet Al2O3 under microwave irradiation in dry media. 相似文献
78.
The effect of amines on the selective bromination of some β-substituted-2-butenoic esters is described. The bromination of methyl (Z)-4-t-butyldiphenylsilyloxy-3-methylbutenoate 2 in the presence of DIPEA (N, N-diisopropylethylamine) and the successive treatment of the obtained dibromide with potassium t-butoxide afford the desired Z bromide selectively. But the corresponding E bromide forms exclusively when 2, 6-di-t-butyl-4-methylpyridine is used in the bromination. 相似文献
79.
The intermolecular [2+2] photocycloaddition of dimedone 6 and 1-acetoxy-2-methyl-5-dioxolan-1-hexene 7 followed by alkaline treatment, gave the 1,5,5,11-tetramethyl-7-dioxolan bicyclo [4,3,2]-4-decen-2,3-dione 12, and the 1,5,5-trimethyl-3-hydroxy-7-dioxolan bicyclo [5,4,1] dodecan-2,11-dione 13. 相似文献
80.
Emanuele Aresu Laura CarrocciaStefania Fioravanti Simona GasbarriLucio Pellacani Fabio Sciubba 《Tetrahedron》2013
Chiral racemic α-diimines, tested in aziridination reactions with NsONHCO2Et, for the first time led to the synthesis of (±)-bidiaziridines, stereoselectively derived from the corresponding meso (E-s-trans-E)-α-diimines. Moreover, a minor bidiaziridine isomer, probably a meso form that was lost under classical work-up conditions, can be obtained by adding water to the crude mixtures at the end of amination reactions. The results definitively prove that the imine aziridination by carbamates is a two-step domino process. The structures of the compounds were determined using 2D NMR on purified bidiaziridines. 相似文献