Darstellung, 11 B-NMR-, Schwingungsspektren und Kristallstruktur von Bis(tetraphenylphosphonium)-2-[2-(2-pyridyl-amino)-pyrid-5-yl]-closo-decaborat, [P(C6H5)4]2[2-{2-(2-(C5H4N)-NH)-(C5H3N)-5}B10H9] / Preparation, 11B NMR, Vibrational Sprectra and Crystal Structure of Bis(tetraphenylphosphonium) 2-[2-(2-Pyridyl-amino)-pyrid-5-yl]-closo-decaborate, [P(C6H5)4]2 [2-{2-(2-(C5H4N)-NH)-(C5H3N)-5}B10H9]

Abstract

By reaction of [N(C4H9)4]2[B10H10] with 2, 2′-(C5H5N)2NH at 160 °C the 2-[2-(2-pyridylamino)- pyrid-5-yl]-closo-decaborate anion [2-{2-(2-(C5H4N)-NH)-(C5H3N)-5 }B10H9]2− is obtained which can be separated from excess [B10H10]2− by ion exchange chromatography on diethylaminoethyl(DEAE) cellulose. The crystal structure of [P(C6H5)4]2[2-{2-(2-(C5H4N)- NH)-(C5H3N)-5 }B10H9] has been determinated by single crystal X-ray diffraction analysis: monoclinic, space group P21/n with a = 11.435(3), b = 22.923(2), c = 20.094(4) Å, β = 95,27(2)°, Z = 4. By influence of the substituent the B10 cage is strongly distorted with B-B distances ranging from 1.522 to 2.188 Å. The 11B NMR spectrum reveals the feature (2:1:7) of a B10 cage with the substituent in the 2 position with a downfield shift of the ipso B atom at −20.2 ppm. The IR and Raman spectra exhibit characteristic BH stretching vibrations between 2416 and 2499 cm −1 and the (C-C) and (C-N) stretching vibrations in the range of 1306 to 1584 cm −1 .