Macrobicyclic Dibridgehead Di(trialkyl)pnictogens E((CH) )E (E/ = As/10, As/12, As/14, Sb/14) and Their Cage-like Metal Complexes: Syntheses, Structures, and Homeomorphic Isomerizations.

Photolyses of -Fe(CO)(As((CH) )As) ( = , 10; , 12; , 14) in the presence of PMe, or reactions of -[Fe(CO)(NO)(As((CH) )As)] BF and -BuN Cl, afford the air stable title complexes As((CH) )As (-) in 79-34% yields. With , the , and , isomers are separable and each is crystallographically characterized. With ,, the isomers rapidly interconvert by homeomorphic isomerization, but each crystallizes (contrathermodynamically) as an , isomer.

Platinum Elimination from Bis(triethylsilylpolyynyl) Complexes (n-BuC(CHPPh))Pt((C≡C)SiEt) (n=2, 3) and Macrocycles Comprised of Four LPt Corners and Four C≡CC≡CC≡C Linkers; An Approach to Cyclo[24]carbon.

The overarching goal of this study is to effect the elimination of platinum from adducts with cis -C≡C-Pt-C≡C- linkages, thereby generating novel conjugated polyynes. Thus, the bis(hexatriynyl) complex trans-(p-tolP)Pt((C≡C)H) is treated with 1,3-diphosphines RC(CHPPh) to generate (RC(CHPPh))Pt((C≡C)H) (14; R=c, n-Bu; e, p-tolCH). These condense with the diiodide complexes RC(CHPPh)PtI (9 a,c) in the presence of CuI (cat.

A Caged Neutral 17-Valence-Electron Iron(I) Radical [Fe(CO)(Cl)(P((CH))P)]: Synthetic, Structural, Spectroscopic, Redox, and Computational Studies.

UV irradiation of yellow CHCl solutions of -Fe(CO)(P((CH))P) () and PMe (10 equiv) gives, in addition to the previously reported dibridgehead diphosphine P((CH))P (46%), a green paramagnetic complex that crystallography shows to be the trigonal-bipyramidal iron(I) radical -[Fe(CO)(Cl)(P((CH))P)] (; 31% after workup). This is a rare example of an isolable species of the formula [Fe(CO)(L)(X)] ( = 0-3, L = two-electron-donor ligand; X = one-electron-donor ligand). Analogous precursors with longer P(CH)P segments ( = 12, 14, 16, 18) give only the demetalated diphosphines, and a rationale is proposed.

Reactions of Platinum Terminal Polyynyl Complexes -(CF)(-tolP)Pt(C≡C)H ( = 2-4) and -BuLi, Generation of Functional Equivalents of Pt(C≡C)Li Species, and Derivatization with Organic and Inorganic Electrophiles.

Reactions of the title complexes and -BuLi (1.5 equiv, -45 °C) afford functional equivalents of the deprotonated species -(CF)(-tolP)Pt(C≡C)Li ( = 2-4), as assayed by subsequent additions of MeI or MeSiCl to give -(CF)(-tolP)Pt(C≡C)Me (66-52%) or -(CF)(-tolP)Pt(C≡C)SiMe (63-49%). However, P NMR data suggest more complicated mechanistic scenarios, and small amounts of the hydride complex -(CF)(-tolP)PtH (independently synthesized from the chloride complex, AgClO, and NaBH) are detected in most cases.

Building Blocks for Molecular Polygons Based on Platinum Vertices and Polyynediyl Edges.

Reactions of ClP(CH)PCl and -MgBrCHX (X = /OMe, /OBu, /Bu, /SiMe) give the diphosphines (-XCH)P(CH)P(-CHX) (-; 47-66%). Additions of , to (COD)PtCl yield (CH(CHP(-CHX)))PtCl (,; 62-88%), which upon reaction with butadiyne (2 equiv; HNEt/cat. CuI) give (CH(CHP(-CHX)))Pt((C≡C)H) (,; 34-76%).