The reaction of terminal phosphinidene complexes [RP–W(CO)₅] with vinylboronic acids is very sensitive to the presence or absence of solid K₃PO₄ in suspension in the reaction medium. The products are phosphirane complexes without the salt and secondary vinylphosphine complexes in the presence of the salt. This shift of the reaction pathway is explained by the formation of vinyborates in the presence of potassium phosphate.

Electrophilic terminal phosphinidene complexes [Ar-Ar-P-W(CO)₅] (Ar-Ar: biaryl or an analogue thereof) undergo a spontaneous insertion of the phosphorus atom into the vicinal CH bonds to give annelated phospholes. Twelve examples are described, including biphenyl, thienyl, pyrrolyl, and benzofuryl groups as biaryl moieties. The activation energy of the insertion reaction is quite low (about 2 kcal mol⁻¹).

The reactions of BX₃ (X = Cl, Br) with 7-R-7-phosphanorbornadiene–M(CO)₅ (M = Mo, W) complexes (1) yields products 2 and 4 in which the RP–M(CO)₅ unit is inserted into one of the carboxyl units of the phthalic derivative as a result of the collapse of the bridge. When X = Br, 4 cyclizes to give new six-membered heterocycles 5 with quasiplanar structures. When treated by an excess of BBr₃, heterocycles 5 undergo ring contraction to afford five-membered oxocyclic products 6.

Aluminum trichloride catalyzes the ring opening of a 1-chlorophosphirane W(CO)₅ complex and its reaction with thiophene and ferrocene to give the corresponding 1-(2-thienyl)- and 1-ferrocenylphosphirane derivatives. The W(CO)₅ complex of the 1-ferrocenylphosphirane is an efficient precursor of the phosphinidene complex [FcP-W(CO)₅], which is trapped by tolan, trans-stilbene, and water.

The discovery and molecular engineering of novel electroluminescent materials is still a challenge in optoelectronics. In this work, the development of new π-conjugated oligomers incorporating a dihydrophosphete skeleton is reported. Variation of the substitution pattern of 1,2-dihydrophosphete derivatives and chemical modification of their P atoms afford thermally stable derivatives, which are suitable emitters to construct organic light-emitting diodes (OLEDs). The optical and electrochemical properties of these new P-based oligomers have been investigated in detail and are supported by DFT calculations. The OLED devices exhibit good performance and current-independent CIE coordinates.

A DFT study suggests that the conversion of arsolylcarbenes into arsenines as described by Märkl proceeds via arsabenzvalenes. A similar conversion does not work with phospholylcarbenes. However, we have found that, in some cases, 1-diazoalkylphosphole sulfides are converted into phosphinine sulfides whose in situ reduction by triphenylphosphite affords the dicoordinate phosphinines.

The reaction of tributylphosphane with a 7-(2′-formyl-2-biphenylyl)phosphanorbornadiene P-W(CO)₅ complex leads to the 5-phosphaphenanthrene P-W(CO)₅ complex via an intramolecular phospha-Wittig condensation. This complex is stable enough for detection by ³¹P NMR spectroscopy but cannot be isolated due to its high reactivity. It is trapped by addition of MeOH or cycloaddition with 2,3-dimethylbutadiene or a nitrileimine. The adducts were characterized by X-ray crystal structure analysis.

The [4+2] cycloadducts between furan compounds and a methylenechlorophosphane pentacarbonyltungsten complex are converted into the corresponding 2-hydroxy- or 2-bromophosphinine complexes by treatment with BBr₃ and triethylamine. The X-ray crystal structure of the parent 2-phosphaphenol complex shows that the hydroxy substituent is coplanar with the ring and that the conjugation between the π lone pair of electrons on the oxygen atom and the ring leads to lengthening of the PC(OH) bond. This complex is methylated at the phosphorus atom by methyl iodide with disruption of the ring aromaticity. The complex is further silylated, acylated, and triflated at the oxygen atom with retention of the aromatic structure, and decomplexation by 1,2-bis(diphenylphosphino)propane (DPPE) leads to the free parent 2-phosphaphenol. The comparison of the X-ray crystallographic structural analysis of the 2-bromophosphinine complex with an earlier structure of the analogous 2-chlorophosphinine complex suggests that 2-bromo species is a better ligand than 2-chlorophosphinine. When the [4+2] adducts are treated with BBr₃ and water, a 2-hydroxy-3-bromo-1,2,3,6-tetrahydrophosphinine derivative is obtained, which yields a seven-membered 2,1-phosphaoxepin when treated with an amine.

Correcting an earlier report, the reaction of 1-phenyl-3,4-dimethylphosphole (1a) with an excess amount of dimethyl acetylenedicarboxylate (DMAD) at room temperature affords the stable cyclopentadienylidenephosphorane 3a resulting from unexpected deoxygenation of initially formed [phosphole + 2DMAD] adduct 2a by the starting phosphole. The identity of 3a was established by X-ray crystal structure analysis. DFT calculations on a model [1+2] adduct similar to 2a shows a bent allenic structure and an ambident reactivity for the terminal carbon of the (DMAD)₂ chain. Cyclopentadienylidenephosphorane 3b is also obtained with 1-benzylphosphole 1b. With 1-stannylphosphole 1c, a 1:3 adduct with a seven-membered ring (i.e., 5) is obtained. It was also characterized by X-ray crystal structure analysis. Finally, with 1-benzyl-2-benzoylphosphole 1d, the P lone pair has lost its nucleophilicity and a [4+2] cycloaddition takes place with the dienol tautomer of the unsaturated ketone to give phosphindole 6, also characterized by X-ray.