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Vugts DJ Jansen H Schmitz RF de Kanter FJ Orru RV 《Chemical communications (Cambridge, England)》2003,(20):2594-2595
In a multi-component reaction (MCR) of a phosphonate, nitriles, aldehydes and isocyanates, N3-functionalised dihydropyrimidines can be synthesised efficiently via a Horner-Emmons/aza Diels-Alder pathway. 相似文献
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Yvar Van Den Winkel Jeroen Van Der Laarse Frans J. J. De Kanter Thomas Van Der Does Friedrich Bickelhaupt Wilberth J. J. Smeets Anthony L. Spek 《Heteroatom Chemistry》1991,2(1):17-28
The synthesis of 2,2′-bis(bis(dimethylamino)-phosphino)-3,3′5,5′-tetra-tert-butylbiphennyl ( 5 ) is described. It was extensively studied by 1H, 13C, and 31P NMR spectroscopy. Furthermore, the X-ray analysis of 5 is reported. Crystals of 5 are tetragonal, space group P¯421c, a = b = 24.770 (3) Å, c = 12.658 (4) Å, Z = 8. The surprising reaction of 5 with proton acids leading to the formation of various phosphorus containing five- and six-membered ring compounds is discussed. On reaction of one of the six-membered ring compounds ( 9 ) with magnesium in THF, a λ3, λ5-diphosphaphenanthrene ( 19 ) was obtained. 相似文献
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Nixon M Friedman M Ronen E Friesem AA Davidson N Kanter I 《Physical review letters》2011,106(22):223901
We experimentally investigate the phase dynamics of laser networks with homogenous time-delayed mutual coupling and establish the fundamental rules that govern their state of synchronization. We identified a specific substructure that imposes its synchronization state on the entire network and show that for any coupling configuration the network forms at most two synchronized clusters. Our results indicate that the synchronization state of the network is a nonlocal phenomenon and cannot be deduced by decomposing the network into smaller substructures, each with its individual synchronization state. 相似文献
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Slootweg JC Vlaar MJ Vugts DJ Eichelsheim T Merhai W de Kanter FJ Schakel M Ehlers AW Lutz M Spek AL Lammertsma K 《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,11(16):4808-4818
Reaction of the transient phosphinidene complexes R-P=W(CO)5 with N-substituted-diphenylketenimines leads unexpectedly to the novel 2-aminophosphindoles, as confirmed by an X-ray crystal structure determined for one of the derivatives. Experimental evidence for a methylene-azaphosphirane intermediate was found by using the iron-complexed phosphinidene iPr2N-P=Fe(CO)4, which affords the 2-aminophosphindole together with the novel methylene-2,3-dihydro-1H-benzo[1,3]azaphosphole. Analysis of the reaction pathways with DFT indicates that the initially formed methylene-azaphosphirane yields both phosphorus heterocycles by way of a [1,5]- or [1,3]-sigmatropic shift, respectively, followed by a H-shift. Strain underlies both rearrangements, which causes these remarkably selective conversions that can be tuned by changing the substituents. 相似文献