6829-52-3

Basic information

• Product Name: methylidynephosphane
• CAS NO: 6829-52-3
• Molecular Formula: CHP
• Molecular Weight: 43.9924
• Mol File: 6829-52-3.mol

Chemical Properties

• CAS DataBase Reference: methylidynephosphane(CAS DataBase Reference)
• NIST Chemistry Reference: methylidynephosphane(6829-52-3)
• EPA Substance Registry System: methylidynephosphane(6829-52-3)

Safety Data

• Hazardous Substances Data: 6829-52-3(Hazardous Substances Data)

Upstream product

• 16523-89-0 triallylphosphine 
• 18148-58-8 Trimethylsilylmethylphosphonigsaeuredichlorid 
• 1498-40-4 dichlorophosphinoethane 
• 78129-68-7 2,2-dimethylpropylidynephosphine 
• 4206-94-4 methylphosphinic acid 
• 676-83-5 methyldichlorophosphane 

Downstream Products

• 42226-36-8 1H-1,2,4-λ³-diazaphosphole 
• 118806-67-0 2,8-diphenyl-3,7-diaza-4,6-dioxa-1-phosphabicyclo<3.3.0>octa-2,7-dien 

Relevant articles and documents

Reinvestigation of the HCP electronic spectrum: Experimental determination of D0 for the X state and observation of hyperfine quantum beats in the B state

In the laser-induced fluorescence spectrum of HCP, a sharp decrease in fluorescence intensity was observed at 41 680 cm-1.This diminuation in emission intensity is due to a rotationally mediated coupling of the excited vibronic level with the dissociative continuum of the X state; this has allowed us to place an upper limit on D0 for the ground electronic state.A lower limit for D0 can be placed at 41 650 cm-1 since strong emission was observed below this excitation energy.Using the assignments of Johns et al. as a guide, fluorescence decays were recorded from the two B state vibronic bands to determine lifetimes.In addition to determining an unusually long lifetime for both states, the decays were seen to be modulated at four frequencies resulting from the coherent excitation of four nuclear hyperfine levels.This increase in lifetime and magnetic hyperfine interaction arises from a mixing of three singlet and triplet states.The contributing states are tentatively identified.

A Molecular Precursor to Phosphaethyne and Its Application in Synthesis of the Aromatic 1,2,3,4-Phosphatriazolate Anion

Dibenzo-7-phosphanorbornadiene Ph3PC(H)PA (1, A = C14H10, anthracene) is reported here as a molecular precursor to phosphaethyne (HC≡P), produced together with anthracene and triphenylphosphine. HCP generated by thermolysis of 1 has been observed by molecular beam mass spectrometry, laser-induced fluorescence, microwave spectroscopy, and nuclear magnetic resonance (NMR) spectroscopy. In toluene, fragmentation of 1 has been found to proceed with activation parameters of δH? = 25.5 kcal/mol and δS? = -2.43 eu and is accompanied by formation of an orange insoluble precipitate. Results from computational studies of the mechanism of HCP generation are in good agreement with experimental data. This high-temperature method of HCP generation has pointed to new reaction chemistry with azide anion to produce the 1,2,3,4-phosphatriazolate anion, HCPN3-, for which structural data have been obtained in a single-crystal X-ray diffraction study. Negative-ion photoelectron spectroscopy has shown the adiabatic detachment energy for this anion to be 3.555(10) eV. The aromaticity of HCPN3- has been assessed using nucleus-independent chemical shift, quantum theory of atoms in molecules, and natural bond orbital methods.

FLASH THERMOLYSIS OF FUNCTIONALISED PHOSPHIRANES

A series of functionalized parent phosphiranes are prepared from the 1-chloro compound.The thermolysis of 1-alkenyl-phosphiranes at 700 deg C produces phosphaalkynes via the rearrangement of vinylphosphinidenes.Methylidynephosphine is obtained by thermolysis of cyclopropylphosphirane.

Synthesis of the Parent Phosphinine and Phosphaalkyne by Flash Thermolysis of Vinyldiallyl- and Triallyl-phosphine

The parent phosphinine is obtained in ca. 40percent yield by thermolysis of vinyldiallylphosphine at 700 deg C at 10-3 Torr; under the same conditions, triallylphosphine mainly yields HCP which can be purified by trap-to-trap distillation.

PRINCIPLES OF PHOSPHORUS CHEMISTRY

An up-to-date concept of bonding in phosphorus compounds has to be based on the reality of molecular states.Molecules, which change their structure with energy, at present are best rationalized in terms of topology and symmetry, effective nuclear potentials and charge distribution.To reduce the complexity of the resulting manifold, comparison of equivalent states of chemical calculations, is strongly recommended.Adding the time-scale, molecular dynamics within the numerous degrees of freedom become important, also as a basis to gain some understanding og the rather complex microscopic reaction pathways of medium-sized molecules.Examples are presented to illustrate the use of spectroscopic "fingerprints" for the analysis and optimization of gasphase reactions as well as the benefit of inherent information on molecular states for the preparative phosphorus chemist.The catalytic dehydrochlorination of alkyldichlorophosphanes RH2C-PCl2 -> RHC=PCl -> R-CP and their dechlorination on magnesium metal surface are discussed in some detail as well as the generation of other unsaturated phosphorus molecules like Cl-P=O, Cl-P=S, ClP(=O)2, Cl-P(=S)2 or H3C-P=CH2.Approximate energy hypersurface calculations for the gasphase equilibrium P4 = 2P2 or for the unexpected dehydration (H3C)2HP=O -> H2O + H3C-P=CH2, which includes chemical activation, provide some insight into microscopic reaction pathways of phosphorus compounds.

OBERFLAECHEN-REAKTIONEN 15 Heterogene Dechlorierungen von Phosphorchloriden (X)PCl3 und R-PCl2 an , , x/TiO2> und sowie spektroskopische Evidenz fuer das Entstehen von Diphospha-dicyan PC-CP aus Cl2P-CC-PCl2

Stimulated by the successful generation of unsaturated molecules with low-coordinated phosphorus centers by heterogeneous surface dechlorination, Cl2P-CC-PCl2 is synthesized and characterized by PE and mass spectra.In addition, curls, wool and catalysts x/TiO2> or are tested as potential dechlorinating agents for phosphorus halides like OPCl3, SPCl3, H3C-PCl2, H5C2-PCl2, (H3C)3C-PCl2 or H5C6-PCl2 in a gasflow reactor under reduced pressure and yield, inter alia, the following representative results: due to the thermodynamically favored formation of , or at the Mg surface, P4 is the only gaseous product identified from reactions of OPCl3 and SPCl3 with metal at higher temperatures.On the contrary, passing H3C-PCl2 at 600K over yields a reaction mixture containing P(CH3)3, (H3C)2P-P(CH3)2 (H3C-P)5 and CH4, which suggests an intermediate formation of surface phosphinidenes Mg>.Analogously, the pentamer (H3C-H2C-P)5 can be isolated from ethyldichlorophosphane.Reaction of the evaporated diphospha-cyanogen precursor Cl2P-C-PCl2 with the catalyst produces predominantly PCl3, and P4, but PE and mass spectra provide evidence that also minor amounts of the hitherto unknown molecule PC-CP are formed.

Ungewoehnlich koordinierte Phosphorverbindungen XXIV. Methylidinphosphan (HCP), ein neuer Cycloadditionspartner fuer 1,3-Dipole

Methylidynephosphane (2) is generated under flash pyrolytic conditions by cleavage of isobutene from the phosphaalkyne (1) or by elimination of hydrogen chloride from dichloromethylphosphine (3).It undergoes -cycloaddition reactions with stable dipoles eq. diazo compounds (2+4a,b->5a,b), methyl azide (2+7->8), benzonitriloxide (2+10->12, 1:2-adduct) and 3-methyl-2,4-diphenyl-1,3-oxazolium-5-olate (2+13->15) to give the corresponding phospholes.Silylated phosphaalkene (19) can be used as a synthetic substitute for 2: the 5-trimethylsilyl-1H-1,2,4-diazaphospholes (22), which result from the reaction of 19 and the diazo compound 4 with chlorotrimethylsilane elimination, are desilylated to 5 by potassium fluoride in dimethyl formamide.

Gas-Phase Infrared Spectra of the Unstable Phosphaalkenes CF2=PH, CF2=PCF3, and CH2=PCl: The C=P Stretching Vibration and Force Constant.

Gas-phase infrared spectra of the unstable phosphaalkenes CF2=PH, CF2=PCF3, and CH2=PCl and their deuteriated species have been measured and vibrational assignments have been made.The C=P stretching bands are observed at 1349.5, 1350.2, and 1365.3 cm-1 for CF2=PH, CF2=PD, and CF2=PCF3, respectively, and at 979.7 and 847.9 cm-1 for CH2=PCl and CD2=PCl, respectively.Normal coordinates were treated for these molecules.For the fluorophosphaalkenes, the C=P stretching mode is highly coupled with the CF2 symmetric stretching mode; one of the coupled vibrations is shifted to higher wavenumber of about 1350 cm-1 and the other to lower wavenumber of about 730 cm-1.For CH2=PCl, the C=P stretching vibration of 979.7 cm-1 is almost negligibly perturbed by other vibrational modes, so that it gives an almost intrinsic C=P stretching wavenumber.For CD2=PCl, the C=P stretching mode is coupled largely with the CD2 scissoring mode.The band intensities of the C=P stretching vibration have also been discussed.The C=P stretching force constant was determined to be 562-668 N m-1.The values for the carbon-phosphorus force constants of the double and triple bonds are roughly two and three times, respectively, as large as the value for the single bond, and the values for the carbon-phosphorus bonds are about half the values for the corresponding carbon-nitrogen bonds.

UNHINDERED PHOSPHAALKENES AND PHOSPHAALKYNES IN STABLE CONDITION FROM A VACUUM MULTISTEP SEQUENCE.

Unhindered low coordinated phosphines 5-6 are obtained in stable condition starting from dichlorophosphines 3 and 4 by a Flash Vacuum Thermolysis/Gas Solid Reaction sequence (FVT/GSR) and fully characterized by 1H, 13C and 31P NMR spectroscopy.