The protonation and methylation of phenylphosphine (C6H5PH2) and its mono-halogenated derivatives have been studied using ab initio quantum chemical calculations. Density functional theory (B3LYP) calculations using the 6-311++G(d,p) basis set consistently confirm that protonation of phenylphosphines takes place at the phosphorus atom; the C4-protonated phenylphosphine lying about 66 kJ mol−1 above the P-protonated isomer. Similarly, methylation of phosphines consistently occurs at phosphorus. The proton and methyl cation affinities are estimated as follows: PA(phenylphosphine) = 863 ± 10 kJ mol−1 and MCA(phenylphosphine) = 515 ± 12 kJ mol−1. Mono-halogen substitution appears to reduce the proton affinites by up to 20 kJ mol−1. In this context, following P-protonation of either a meta- or a para-X–C6H4–PH2, an elimination of the halogen X-atom under collisional activation (CA) conditions is expected to lead to a distonic radical cation, a low-energy isomer being 50 kJ mol−1 above ionized phenylphosphine.
FlammangR.PlisnierM.LeroyG.SanaM.NguyenM.T.VanquickenborneL.G., “The Distonic HC+(OH)OCH2• Radical Cation: A Stable Isomer of Ionized Methyl Formate”, Chem. Phys. Lett.186, 393–400 (1991).
2.
NguyenM.T.VanquickenborneL.G.PlisnierM.FlammangR., “A Mass Spectrometric and Ab Initio Molecular Orbital Characterization of Thionitrosyl Hydride (H–N=S)”, Mol. Phys.78, 111–119 (1993).
3.
NguyenM.T.VanquickenborneL.G.FlammangR., “The Thionitrosyl Free Radical (H2NS) and Its Ionic Counterparts (H2NS+ and H2NS−). A Theoretical and Experimental Study”, J. Chem. Phys.101, 4885–4892 (1994).
4.
NguyenM.T.FlammangR.GoldbergN.SchwarzH., “The Gas Phase Nitrogen Disulfide Radical (SNS)”, Chem. Phys. Lett.236, 201–205 (1995).
5.
NguyenM.T.FlammangR., “A Theoretical Study of Thionitrosyl Azide (N3–N=S), Thiazyl Azide (N3–S=N) and Nitrosyl Azide (N3–N=O)”, Chem. Ber.129, 1373–1377 (1996).
6.
NguyenM.T.FlammangR, “A Search for Thionitrosyl Chloride (Cl–N=S) in the Gas Phase”, Chem. Ber.129, 1379–1381 (1996).
7.
LahemD.FlammangR.Van HaverbekeY.NguyenM.T., “On the Loss of SH from the Molecular Ions of S-alkyl Thioformates: Experimental Evidence for the Generation of Hydroxycarbenium Ions”, Rapid Commun. Mass Spectrom.11, 373–377 (1997).
8.
LahemD.FlammangR.NguyenM.T., “Observation of Thiohydroxy-hydroxy-carbene [HS–C–OH] when Searching for Thionformic Acid [HC(=S)OH] in the Gas Phase”, Chem. Phys. Lett.270, 93–98 (1997).
9.
FlammangR.LahemD.NguyenM.T., “Novel β-Distonic Radical Cations [CnH2n+2S]•+ (n =2, 3) Formed upon Decarbonylation of Ionized S-Alkyl Thioformates: A Mass Spectrometric and ab Initio Study”, J. Phys. Chem. A101, 9818–9823 (1997).
10.
FlammangR.LahemD.NguyenM.T., “On the Loss of Water from the Molecular Ions of S-Alkyl Thioformates”, Bull. Soc. Chim. Belges106, 709–716 (1997).
GerbauxP.FlammangR.NguyenM.T.SalpinJ.Y.BouchouxG., “Formation and Characterization of Acetonitrile N-methylide [CH3CNCH2]•+ and N-methylketenimine [CH3NCCH2]•+ Radical Cationsin the Gas Phase”, J. Phys. Chem. A102, 861–869 (1998).
13.
NguyenM.T.LahemD.FlammangR., “The Gas Phase RnX-NO+ (X = O,N,S) Cations: Nitroso Onium Cations versus Ion–Molecule Complexes”, Chem. Phys. Lett.283, 357–362 (1998).
14.
LahemD.FlammangR.LeH.T.NguyenM.T., “The Gas Phase Sulfur-Containing Distonic Radical Cation HC+(OH)SCH2•”, Rapid Commun. Mass Spectrom.12, 1972–1975 (1998).
15.
LahemD.FlammangR.LeH.T.NguyenT.L.NguyenM.T., “[C2H4OS]•+ Radical Cations Derived from Alkyl Thioformates: Tandem Mass Spectrometry and Molecular Orbital Calculations”, J. Chem. Soc., Perkin Trans. 2821–826 (1999).
16.
LeH.T.NguyenT.L.LahemD.FlammangR.NguyenM.T., “Potential Energy Surfaces Related to Thioxy-hydroxy-carbene (HS–C–OH) and Its Radical Cation”, Phys. Chem.-Chem. Phys.1, 755–760 (1999).
17.
SalpinJ.Y.NguyenM.T.BouchouxG.GerbauxP.FlammangR., “Isomerization of Acetonitrile N-methylide [CH3CNCH2]•+ and N-methylketenimine [CH3NCCH2]•+ Radical Cations in the Gas Phase: Theoretical Study of the [C3,H5,N]•+ Potential Energy Surface”, J. Phys. Chem. A103, 938–946 (1999).
18.
FlammangR.HenrotteV.GerbauxP.NguyenM.T., “Collisional Interaction of Ionized Pyridine N-oxides with Various Targets in a New Hybrid Mass Spectrometer”, Eur. J. Mass Spectrom.6, 3–9 (2000).
19.
FlammangR.Barbieux-FlammangM.LeH.T.NguyenM.T.BerthelotJ.TortajadaJ., “Dehalogenation of Protonated 1,2,4-Triazoles: Synthesis of New Heterocyclic Carbenic and Ylide Radical Cations and Contrasting Behaviour of Collision Gases”, Int. J. Mass Spectrom.199, 221–233 (2000).
20.
LeH.T.GerbauxP.FlammangR.NguyenM.T., “Collisional Activation of Protonated Halogenopyridines: Different Behaviour of Target Gases”, Chem. Phys. Lett.323, 71–78 (2000).
21.
FlammangR.NguyenM.T.BouchouxG.GerbauxP., “Characterization of Ionized Carbenes in the Gas Phase”, Int. J. Mass Spectrom.202, A8–A25 (2000).
22.
FlammangR.Van HaverbekeY.GerbauxP.NguyenM.T., “Evidence for the Production of Propene Ion in the Gas Phase. Reaction of Ionized Dichlorocarbene with Acetone”, Tetrahedron Lett.42, 669–671 (2001).
23.
GerbauxP.SciamannaV.FlammangR.NguyenM.T., “High-energy Collisional Activation of the Molecular Ions of Thiophene-2-one with Different Target Gases”, J. Mass Spectrom.36, 97–101 (2001).
24.
FlammangR.Barbieux-FlammangM.GualanoE.GerbauxP.LeH.T.NguyenM.T.TurečekF.VivekanandaS., “Ionized Benzonitrile and its Distonic Isomers in the Gas Phase”, J. Phys. Chem. A105, 8579–8587 (2001).
LeH.T.FlammangR.GerbauxP.BouchouxG.NguyenM.T., “Ionized Phenol and its Isomers in the Gas Phase”, J. Phys. Chem. A105, 11528–11539 (2001).
27.
HajgatoB.FlammangR.VeszpremiT.NguyenM.T., “Experimental and Theoretical Study of Dicyanocarbene C(CN)2”, Mol. Phys.100, 1693–1702 (2002).
28.
FlammangR.ElgueroJ.LeH.T.GerbauxP.NguyenM.T., “Collisional Induced Loss of NO2 Radical from Protonated Nitroimidazoles and Nitropyrazoles”, Chem. Phys. Lett.356, 259–266 (2002).
29.
FlammangR.Barbieux-FlammangM.GualanoE.GerbauxP.LeH.T.NguyenM.T.TurečekF., “Distonic Isomers of Ionized Benzaldehyde”, Int. J. Mass Spectrom.217, 65–73 (2002).
30.
LeH.T.FlammangR.Barbieux-FlammangM.GerbauxP.NguyenM.T., “Ionized Aniline and Its Distonic Radical Cations Isomers”, Int. J. Mass Spectrom.217, 45–54 (2002).
31.
NamP.C.FlammangR.LeH.T.GerbauxP.NguyenM.T., “Protonation of Thiophenol, Thioanisole and their Halogenated Derivatives: A Mass Spectrometric and ab initio Computational Study”, Int. J. Mass Spectrom., in press (2003).
32.
NguyenM.T.NguyenT.L.MebelA.M.FlammangR., “Azido-Nitrene is Probably the N4 Species Observed in Mass Spectrometric Experiment”, J. Phys. Chem. A107, 5452–5460 (2003).
33.
BatemanR.H.BrownJ.LefevereM.FlammangR.Van HaverbekeY., “Applications in gaseous ion and neutral chemistry using a 6-sector mass spectrometer”, Int. J. Mass Spectrom. Ion Processes115, 205–218 (1992).
34.
BouchouxG.FlammangR.JaudonP.LefevreO., “Gas-phase unimolecular chemistry of ethyl butyl ketone cations”, Org. Mass Spectrom.28, 1189–1196 (1993).
35.
FlammangR.Van HaverbekeY.BraybrookC.BrownJ., “A new hybrid mass spectrometer for the investigation of ion/molecule reactions”, Rapid Commun. Mass Spectrom.9, 795–799 (1995).
36.
GerbauxP.Van HaverbekeY.FlammangR., “Ion–molecule reaction of pyridine with CS3 radical cations: Experimental evidence for the production of pyridine N-thioxide distonic ions”, J. Mass Spectrom.32, 1170–1178 (1997).
37.
FlammangR.LaurentS.Barbieux-FlammangM.WentrupC., “Characterization of iminopropadienone ions and neutrals in a tandem mass spectrometer”, Rapid Commun. Mass Spectrom.6, 667–670 (1992).
38.
FlammangR.LanduD.LaurentS.Barbieux-FlammangM.KappeC.O.WongM.W.WentrupC., “Iminoethenethiones, RN=C=C=S, characterization by neutralization–reionization mass spectrometry and G2(MP2) theory”, J. Am. Chem. Soc.116, 2005–2013 (1994).
39.
LarsenN.W.SteinarssonT., “Conformation, Barrier to Internal Rotation and Structure of the PH2-Group in Phenylphosphine Studied by Microwave Spectroscopy”, J. Mol. Spectrosc.123, 405–425 (1987).
40.
DebiesT.P.RabalaisJ.W., “Photoelectron Spectra of Substituted Benzenes. III. Bonding with Group V Substituents”, Inorg. Chem.13, 308–312 (1974).
41.
NyulasziL.SzieberthD.CsonkaG.I.ReffyJ.HeinickeJ.VeszpremiT., “The Photoelectron Spectrum and Conformation of Phenylphosphine and Phenylarsine”, Struct. Chem.6, 1–7 (1995).
42.
IkutaS.KebarleP., “A Comparison of Methyl and Phenyl Substituent Effects on the Gas Phase Basicities of Amines and Phosphines”, Can. J. Chem.61, 97–102 (1983).
43.
LiR.SmithR.L.KenttämaaH.I., “Fluorine Substitution Enhances the Reactivity of Substituted Radicals toward Organic Hydrogen Atom Donors”, J. Am. Chem. Soc.118, 5056–5061 (1996).
44.
ThoenK.K.SmithR.L.NousiainenJ.J.NelsonE.D.KenttämaaH.I., “Charges Phenyl Radicals”, J. Am. Chem. Soc.118, 8669–8676 (1996).
45.
LeclercE.BuchmannW.TaphanelM.H.MorizurJ.P., “Gas-phase Ion–Molecule Reactions between Dimethoxyphosphonium Ions and Aromatic Hydrocarbons”, Rapid Commun. Mass Spectrom.16, 686–695 (2002).
46.
FrischM.J.TrucksG.W.SchlegelH.B.GillP.M.W.JohnsonB.G.RobbM.A.CheesemanJ.R.KeithT.A.PeterssonG.A.MontgomeryJ.A.RaghavachariK.Al-LahamM.A.ZakrzewskiV.G.OrtizJ.V.ForesmanJ.B.PengC.Y.AyalaP.Y.WongM.W.AndresJ.L.ReplogleE.S.GompertsR.MartinR.L.FoxD.J.BinkleyJ.S.DeFreesD.S.BakerJ.StewartJ.P.Head-GordonM.GonzalezC.PopleJ.A., Gaussian 94, Rev. C3. Gaussian Inc., Pittsburgh, PA (1995).
47.
TishchenkoO.Pham-TranN.N.KryachkoE.S.NguyenM.T., “Protonation of Gaseous Halogenated Phenols and Anisoles and Its Interpretation Using DFT-Based Local Reactivity Indices”, J. Phys. Chem. A105, 8709–8717 (2001).
48.
BouchouxG.DefayeD.McMahonT.LikholyotA.MoO.YanezM., “Structural and Energetic Aspects of the Protonation of Phenol, Catechol, Resorcinol and Hydroquinone”, Chem., Eur. J.8, 2900–2909 (2002).
