含氧钼（IV）配合物的电子吸收光谱和磷光

Electronic Absorption Spectra and Phosphorescence of Oxygen-Containing Molybdenum(IV) Complexes.

作者信息

Isovitsch Ralph A., Beadle A. Scott, Fronczek Frank R., Maverick Andrew W.

机构信息

Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803-1804.

出版信息

Inorg Chem. 1998 Aug 24;37(17):4258-4264. doi: 10.1021/ic971186e.

DOI:10.1021/ic971186e

PMID:11670560

Abstract

Electronic absorption and emission spectra are reported for salts of two oxomolybdenum(IV) cations, MoOCl(CN-t-Bu)(4) and MoOCl(Ph(2)PCH(2)CH(2)PPh(2))(2), and for the new Mo(IV) complex trans-Mo(OCH(3))(2)(CN-t-Bu)(4). All three ions show absorption bands (lambda(max,abs) 550-570 nm; epsilon 45-120 M(-)(1) cm(-)(1)) attributable to the (1)A(1)[(d(xy)())(2)] --> (1)E[(d(xy)())(1)(d(xz)()(,)(yz)())(1)] (C(4)(v)()) transition, and the last two show weak shoulders in the 700-750 nm range due to the analogous spin-forbidden ((1)A(1) --> (3)E) transition. Phosphorescence (lambda(max,em) 850-960 nm) occurs in the solid state for all three compounds at both room temperature and 77 K, and for MoOCl(CN-t-Bu)(4) in CH(2)Cl(2) at room temperature. These are the first phosphorescences recorded for molybdenum(IV) complexes. MoOCl(CN-t-Bu)(4) precipitates quickly if NaBPh(4) is added to the Mo(IV) solution prepared from MoCl(5) and tert-butyl isocyanide in CH(3)OH. However, if NaPF(6) is used instead, trans-Mo(OCH(3))(2)(CN-t-Bu)(4)(2) (formed by reaction of MoOCl(CN-t-Bu)(4) with methanol) crystallizes over a period of ca. 24 h. The crystal structure of trans-Mo(OCH(3))(2)(CN-t-Bu)(4)(2) has been determined: C(22)H(42)F(12)MoN(4)O(2)P(2), monoclinic; space group P2(1)/c; a = 9.1538(8) Å, b = 15.709(2) Å, c = 13.456(2) Å; beta = 103.31(1) degrees; Z = 2; R(F) = 0.063, R(w)(F) = 0.056 for 2719 reflections with I > sigma(I).

摘要

报道了两种氧代钼（IV）阳离子盐[MoOCl(CN-t-Bu)(4)]⁺和[MoOCl(Ph₂PCH₂CH₂PPh₂)(2)]⁺以及新的钼（IV）配合物[trans-Mo(OCH₃)(2)(CN-t-Bu)(4)]²⁺的电子吸收光谱和发射光谱。所有这三种离子都显示出归因于(¹A₁[(dxy)²] → (¹E[(dxy)¹(dxz,yz)¹]) (C₄ᵥ)跃迁的吸收带（λmax,abs 550 - 570 nm；ε 45 - 120 M⁻¹ cm⁻¹），并且后两种在700 - 750 nm范围内显示出由于类似的自旋禁阻（¹A₁ → ³E）跃迁导致的弱肩峰。所有三种化合物在室温及77 K下固态时都有磷光（λmax,em 850 - 960 nm），并且[MoOCl(CN-t-Bu)(4)]⁺在室温下的二氯甲烷中也有磷光。这些是首次记录到的钼（IV）配合物的磷光。如果将NaBPh₄加入到由MoCl₅和叔丁基异腈在甲醇中制备的钼（IV）溶液中，[MoOCl(CN-t-Bu)(4)]BPh₄会迅速沉淀。然而，如果使用NaPF₆代替，trans-Mo(OCH₃)(2)(CN-t-Bu)(4)₂（由[MoOCl(CN-t-Bu)(4)]⁺与甲醇反应形成）会在大约24小时内结晶。已确定trans-Mo(OCH₃)(2)(CN-t-Bu)(4)₂的晶体结构：C₂₂H₄₂F₁₂MoN₄O₂P₂，单斜晶系；空间群P2₁/c；a = 9.1538(8) Å，b = 15.709(2) Å，c = 13.456(2) Å；β = 103.31(1)°；Z = 2；对于2719个I > σ(I)的反射，R(F) = 0.063，R(w)(F) = 0.056。