Lewis Base Adducts of Lead(II) Compounds. I. Polymer Isomerism in Some 1-2 Adducts of Lead(II) Halides With Pyridine Bases

Abstract

Recrystallization of lead(II) halides, PbX2 (X = C1, Br, I), from n- methylpyridine, n = 3, 4, yields crystalline 1 : 2 adducts; these have all been shown by single-crystal X-ray structure determination to contain the lead in an essentially octahedral six-coordinate environment, two of the coordination sites being occupied by monodentate pyridine base moieties and four by bridging halogen, yielding infinite polymeric arrays. For X = Cl, Br, n = 3, the nitrogen atoms lie cis in the coordination sphere; for the other complexes, they are trans. In the two cis complexes, distortion from ideal orthogonal geometry is more substantial than in the trans, possibly indicative of the presence of a sterically active 'lone pair'.

Synthesis and Characterization of a Quasi‐One‐Coordinate Lead Cation

“…The PbÀC(ipso) bond distance increases to 2.313(5) (compared with 2.251(7) in 1), which is consistent with the higher lead coordination number. The PbÀN bond lengths (2.409(5) and 2.512(5) ) are similar to those seen in [Pb(Br)Ar*]·py (2.502(4) ), [31] and are much shorter than those found in the PbBr 2 complexes [{(4-MeH 4 C 5 N) 2 ·PbBr 2 } n ] [38] and [{(3-MeH 4 C 5 N) 2 ·PbBr 2 } n ] (both 2.60(2) ), [38] and in the plumbocene-pyridine complexes [Pb(h 5 [39] which have higher effective coordination numbers at their Pb centers. The 207 Pb NMR chemical shift of 2 is at % 4000 ppm higher field compared to 1, which is consistent with an increase in coordination number from one to three.…”

Ionothermal synthesis, structure and optical properties of three new organic–inorganic hybrid imidazolium bromoplumbate complexes

“…Among the various metal-halide systems, lead(II) halides have a significant position. The obtained structures of lead(II) halides are sporadic and various, showing a wide variety of coordination numbers and stereochemistries with or without the suggestion of a "lone pair" in the coordination sphere [23]. Moreover, tremendous progress has been made to achieve different dimensions of lead halide polyanions by exploring the organic templates.…”

Isomers in the Chemistry of Lead Compounds

“…A: Two Independent Molecules (7) 16.131 (6) 12.889 (5) 9.576(2) 14.151 (4) 16.175 (4) 9.08(1) 11.26(1) 17.14(1) 6.343 (2) 12.286 (5) 16.593 (6) 9.720(1) 10 Footnotes: a. Where more than one chemically equivalent distance or angle is present, the mean value is tabulated.…”

“…Brought to you by | University of Arizona Authenticated Download Date | 6/7/15 12:03 PM (6) S,S 72.6(2)" 2.864 (6,14) 95.6(2) 3.000 (6) 95.7 (2) Pb"N 4 η 4 ,Ν 2.62(3,10) Ν,Ν 76.1 (9,4.0)' 30 η 4 ,Ν 2.62 (3,10) 121.3 (8,9) Pb"N 4 η 4 ,Ν 2.55(3,30) Ν,Ν 75.8 (9,9. …”