The nuclear magnetic resonance spectra of phosphabenzene, arsabenzene, and stibabenzene

High resolution NMR spectroscopy of heteroaromatic cations. II—pyrylium, thiapyrylium and seleninium cations

“…protons with increasing periodic number of the heteroatom in a recent study on group V heteroaromatic compounds (pyridine, phosphabenzene, arsabenzene and stilbabenzene). 16 The observed and calculated anisotropy effects varied from approximately 2 ppm in phosphabenzene to 3 ppm in arsabenzene. These figures are in good qualitative agreement with the values estimated from the chemical shift data in Table 1 In a similar manner to the 5-membered neutral heteroaromatics, proton-proton couplings in the cations seem to be primarily affected by the electronegativity of the heter0at0m.l~ An increase in its electronegativity causes 3J(H-2, H-3), 3J(H-3, H-4) and 4J(H-2, H-6) to decrease and 4J(H-2, H-4) and 4J(H-3, H-5) to increase.…”

Computational NMR Spectroscopy of Organoarsenicals and the Natural Polyarsenic Compound Arsenicin A

“…; [25] trimethylarsine ylide, (CH 3 ) 3 As=CH 2 (4); [26,27] trimethylarsine, (CH 3 ) 3 As (5); [28] triphenylarsine, Ph 3 As (6); [28] arsabenzene, C 5 H 5 As (7); [29] …”

Evidence for the generation and trapping of a silabenzene

“…Then, in 1966, Markl by dehydrohalogenation of the corresponding cycloheterohalodiene (7). These compounds provide an excellent opportunity to determine information about aromatic heterocycles and multiple bonds as a function of increasing atomic number (14)(15)(16)(17)(18)(19). A more complete discussion of these com pounds can be found in a review by Jutzi (12).…”