1. For comprehensive works see: F. Mathey, Chem. Rev. 88 (1988) 437; A.N. Hughes, in: R. Engel (Ed.), Handbook of Organophosphorus Chemistry, Marcel Dekker, New York, 1992, Chapter 10; L.D. Quin, in: A. Katritzky, C. Rees, W.E.F.V. Scriven (Eds.), Comprehensive Heterocyclic Chemistry, Vol. 2, Pergamon, Oxford, England, 1996, Vol. 2, pp. 757–856.Aromaticity indices of different type are much smaller for phosphole than for other five membered rings;K.K. Baldridge, M.S. Gordon, J. Am. Chem. Soc. 110 (1988) 4204; L. Nyulászi, T. Veszprémi, J. Réffy, B. Burkhardt, M. Regitz, J. Am. Chem. Soc. 114 (1992) 9080; V.I. Minkin, M.N. Glukhotsev, B.Ya. Simkin, Aromaticity and Antiaromaticity—Electronic and Structural Aspects, Wiley, New York, 1994; P.v.R. Schleyer, P.K. Freeman, H. Jiao, B. Goldfuss, Angew. Chem. Int. Ed. Engl. 34 (1995) 337.
2. Semiempirical calculation of barriers to pyramidal inversion. Extension to the third row of the periodic table
3. Vibrational Energy Level Splitting and Optical Isomerism in Pyramidal Molecules of the Type XY31
4. Characterization of NMR Deshielding in Phosphole and the Phospholide Ion
5. Effects of Substituents on the Aromatization of Phosphole