Institut für Anorganische Chemie, Rheinische Friedrich-Wilhelms-Universität Bonn, Gerhard-Domagk-Strasse 1, D-53121 Bonn, Germany.
Inorg Chem. 2012 Oct 1;51(19):10408-16. doi: 10.1021/ic301641z. Epub 2012 Sep 11.
1-Alkyl-3-methyl-4-diphenylphosphoryl-imidazolium hydrogensulfate (4a,b) (a: R(1) = R(2) = Me; b: R(1) = (i)Pr, R(2) = Me) and 1-alkyl-3-methyl-4,5-bis(diphenylphosphoryl)imidazolium hydrogensulfate (6a,c) (c: R(1) = (n)Bu, R(2) = Me) were obtained selectively and in good yields by oxidative desulfurization of 1-alkyl-3-methyl-4-diphenylphosphino-imidazole-2-thiones (2a,b) and 1-n-butyl-3-methyl-4,5-bis(diphenylphosphoryl)imidazole-2-thione (3c) or 1,3-dimethyl-4-diphenylthiophosphoryl-5-diphenylphosphino-imidazole-2-thione (5a), respectively, with hydrogen peroxide. Synthesis of phosphoryl functionalized imidazol-2-ylidene complexes of group VI metal pentacarbonyls (7a-9a) and (10b-12b) and bis(phosphoryl) functionalized imidazol-2-ylidene complexes of group VI metal pentacarbonyls (13c-15c) and (16a) with low steric demand (methyl, isopropyl, n-butyl) at both N-centers was achieved through deprotonation of imidazolium salts (4a,b) and (6a,c), respectively,-having HSO(4)(-) as a counterion-with potassium tert-butoxide followed by rapid addition of metal pentacarbonyl acetonitrile complexes [M(CO)(5)(CH(3)CN)] (M = Cr, Mo, W). The products were unambiguously characterized by elemental analyses, spectroscopic and spectrometric methods, and in addition, by single-crystal X-ray structure studies in the cases of 4b, 8a, 15c, and 16a; the latter two reveal imidazole ring bond distance alternation in contrast to 8a.
1-烷基-3-甲基-4-二苯基膦酰基咪唑翁硫酸氢盐（4a,b）（a: R(1) = R(2) = Me；b: R(1) = (i)Pr，R(2) = Me）和 1-烷基-3-甲基-4,5-双（二苯基膦酰基）咪唑翁硫酸氢盐（6a,c）（c: R(1) = (n)Bu，R(2) = Me）通过过氧化氢氧化 1-烷基-3-甲基-4-二苯基膦基咪唑-2-硫酮（2a,b）和 1-正丁基-3-甲基-4,5-双（二苯基膦酰基）咪唑-2-硫酮（3c）或 1,3-二甲基-4-二苯基硫代膦酰基-5-二苯基膦基咪唑-2-硫酮（5a），分别选择性地以高收率合成了 6 族金属五羰基的磷酰基功能化咪唑-2-亚基配合物（7a-9a）和（10b-12b）以及双（磷酰基）功能化咪唑-2-亚基配合物（13c-15c）和（16a），这些配合物具有低空间位阻（甲基、异丙基、正丁基），在 N 位中心均具有 HSO(4)(-)作为抗衡离子的咪唑翁盐（4a,b）和（6a,c）。通过用叔丁醇钾对具有 HSO(4)(-)作为抗衡离子的咪唑翁盐（4a,b）和（6a,c）进行脱质子化，然后迅速加入金属五羰基乙腈配合物[M(CO)(5)(CH(3)CN)]（M = Cr、Mo、W），分别得到了它们。通过元素分析、光谱和光谱学方法以及 4b、8a、15c 和 16a 的单晶 X 射线结构研究，对产物进行了明确的表征；后两种情况显示出与 8a 相反的咪唑环键距交替。
