Unusual Reactivity of Methylphosphaalkyne (PCMe) toward Digermenes and Distannenes: Stepwise Formations of Bridged 2,3,5,6-Tetraphospha-1,4-dimethylidenecyclohexanes

Reactions of methylphosphaalkyne, PCMe, with a digermene, R″2GeGeR″2 (R″ = −CH(SiMe3)2), and two distannenes, R″2SnSnR″2 and Ar′2SnSnAr′2 (Ar′ = C6H2Pri3-2,4,6), have given moderate to high yields of the first bridged 2,3,5,6-tetraphospha-1,4-dimethylidenecyclohexanes, [R2E{C(Me)(H)PC(CH2)P}]2 (R = R″ or Ar′, E = Sn or Ge), all of which have been structurally characterized. Their mechanisms of formation are thought to involve successive [2 + 1] and [2 + 2] phosphaalkyne cycloaddition, heterocycle rearrangement, phosphaalkene/vinylphosphine tautomerization, and intermolecular hydrophosphination reactions. In one reaction, two intermediates have been spectroscopically observed and one trapped by coordination to one or two W(CO)5 fragments, yielding the first diphosphagermole complexes, {[W(CO)5}1or2{R″2Ge[C(Me)PC(Me)P]}], which have been structurally characterized. Differences between the reactivities of PCMe and PCBut are highlighted

Unusual Reactivity of Methylphosphaalkyne (PCMe) toward Digermenes and Distannenes: Stepwise Formations of Bridged 2,3,5,6-Tetraphospha-1,4-dimethylidenecyclohexanes

Reactions of methylphosphaalkyne, PCMe, with a digermene, R″2GeGeR″2 (R″ = −CH(SiMe3)2), and two distannenes, R″2SnSnR″2 and Ar′2SnSnAr′2 (Ar′ = C6H2Pri3-2,4,6), have given moderate to high yields of the first bridged 2,3,5,6-tetraphospha-1,4-dimethylidenecyclohexanes, [R2E{C(Me)(H)PC(CH2)P}]2 (R = R″ or Ar′, E = Sn or Ge), all of which have been structurally characterized. Their mechanisms of formation are thought to involve successive [2 + 1] and [2 + 2] phosphaalkyne cycloaddition, heterocycle rearrangement, phosphaalkene/vinylphosphine tautomerization, and intermolecular hydrophosphination reactions. In one reaction, two intermediates have been spectroscopically observed and one trapped by coordination to one or two W(CO)5 fragments, yielding the first diphosphagermole complexes, {[W(CO)5}1or2{R″2Ge[C(Me)PC(Me)P]}], which have been structurally characterized. Differences between the reactivities of PCMe and PCBut are highlighted

Homo- and Heteroleptic Complexes of Four-Membered Group 13 Metal(I) N-Heterocyclic Carbene Analogues with Group 10 Metal(0) Fragments

A series of complexes between recently developed four-membered group 13 metal(I) heterocycles and group 10 metal(0) fragments have been prepared and structurally characterized. One prepared complex, [Pt{Ga[N(Ar)]2CNCy2}3] (Ar = C6H3Pri2-2,6; Cy = cyclohexyl), possesses the shortest Pt−Ga bonds yet reported, the covalent components of which are suggested by theoretical studies to have significant π character

Homo- and Heteroleptic Complexes of Four-Membered Group 13 Metal(I) N-Heterocyclic Carbene Analogues with Group 10 Metal(0) Fragments

A series of complexes between recently developed four-membered group 13 metal(I) heterocycles and group 10 metal(0) fragments have been prepared and structurally characterized. One prepared complex, [Pt{Ga[N(Ar)]2CNCy2}3] (Ar = C6H3Pri2-2,6; Cy = cyclohexyl), possesses the shortest Pt−Ga bonds yet reported, the covalent components of which are suggested by theoretical studies to have significant π character

Homo- and Heteroleptic Complexes of Four-Membered Group 13 Metal(I) N-Heterocyclic Carbene Analogues with Group 10 Metal(0) Fragments

A series of complexes between recently developed four-membered group 13 metal(I) heterocycles and group 10 metal(0) fragments have been prepared and structurally characterized. One prepared complex, [Pt{Ga[N(Ar)]2CNCy2}3] (Ar = C6H3Pri2-2,6; Cy = cyclohexyl), possesses the shortest Pt−Ga bonds yet reported, the covalent components of which are suggested by theoretical studies to have significant π character

Homo- and Heteroleptic Complexes of Four-Membered Group 13 Metal(I) N-Heterocyclic Carbene Analogues with Group 10 Metal(0) Fragments

A series of complexes between recently developed four-membered group 13 metal(I) heterocycles and group 10 metal(0) fragments have been prepared and structurally characterized. One prepared complex, [Pt{Ga[N(Ar)]2CNCy2}3] (Ar = C6H3Pri2-2,6; Cy = cyclohexyl), possesses the shortest Pt−Ga bonds yet reported, the covalent components of which are suggested by theoretical studies to have significant π character

Homo- and Heteroleptic Complexes of Four-Membered Group 13 Metal(I) N-Heterocyclic Carbene Analogues with Group 10 Metal(0) Fragments

A series of complexes between recently developed four-membered group 13 metal(I) heterocycles and group 10 metal(0) fragments have been prepared and structurally characterized. One prepared complex, [Pt{Ga[N(Ar)]2CNCy2}3] (Ar = C6H3Pri2-2,6; Cy = cyclohexyl), possesses the shortest Pt−Ga bonds yet reported, the covalent components of which are suggested by theoretical studies to have significant π character

Heavy Group 15 Element Compounds of a Sterically Demanding Bis(iminophosphorane)methanide and -methanediide

Complexes of the heavy pnictogen elements Sb and Bi of monoanionic (<i>C</i>,<i>N</i>-chelated: Sb, Bi) and dianionic (<i>N</i>,<i>C</i>,<i>N</i>-pincer type: Bi) bulky substituted bis­(diphenyl­(arylimino)­phosphorano)­methane H₂C­(Ph₂PNR)₂ (R = 2,6-diisopropylphenyl (dipp)) have been prepared via metathetical reactions, and tautomerism within the monoanionic ligand backbone has been observed. The complexes have been characterized by means of X-ray analysis and NMR studies. The dianionic complex was found to feature the rare structural motif of a formal carbon–bismuth­(III) double bond. The molecular structure of the solvate-free potassium salt K­[HC­(Ph₂PNdipp)₂] is reported

Heavy Group 15 Element Compounds of a Sterically Demanding Bis(iminophosphorane)methanide and -methanediide

Complexes of the heavy pnictogen elements Sb and Bi of monoanionic (<i>C</i>,<i>N</i>-chelated: Sb, Bi) and dianionic (<i>N</i>,<i>C</i>,<i>N</i>-pincer type: Bi) bulky substituted bis­(diphenyl­(arylimino)­phosphorano)­methane H₂C­(Ph₂PNR)₂ (R = 2,6-diisopropylphenyl (dipp)) have been prepared via metathetical reactions, and tautomerism within the monoanionic ligand backbone has been observed. The complexes have been characterized by means of X-ray analysis and NMR studies. The dianionic complex was found to feature the rare structural motif of a formal carbon–bismuth­(III) double bond. The molecular structure of the solvate-free potassium salt K­[HC­(Ph₂PNdipp)₂] is reported

Experimental Electron Density Study of the Mg−Mg Bonding Character in a Magnesium(I) Dimer

Experimental Electron Density Study of the Mg−Mg Bonding Character in a Magnesium(I) Dime