Salts of the Cobalt(I) Complexes [Co(CO)5]+ and [Co(CO)2(NO)2]+ and the Lewis Acid–Base Adduct [Co2(CO)7COB(CF3)3]

✍ Scribed by Eduard Bernhardt; Maik Finze; Helge Willner; Christian W. Lehmann; Friedhelm Aubke

• Publisher: John Wiley and Sons
• Year: 2006
• Tongue: English
• Weight: 214 KB
• Volume: 12
• Category: Article
• ISSN: 0947-6539
• DOI: 10.1002/chem.200600210

✦ Synopsis

Abstract

The reaction of [Co~2~(CO)~8~] with (CF~3~)~3~BCO in hexane leads to the Lewis acid–base adduct [Co~2~(CO)~7~COB(CF~3~)~3~] in high yield. When the reaction is performed in anhydrous HF solution [Co(CO)~5~][(CF~3~)~3~BF] is isolated. The product contains the first example of a homoleptic metal pentacarbonyl cation with 18 valence electrons and a trigonal‐bipyramidal structure. Treatment of [Co~2~(CO)~8~] or [Co(CO)~3~NO] with NO^+^ salts of weakly coordinating anions results in mixed crystals containing the [Co(CO)~5~]^+^/[Co(CO)~2~(NO)~2~]^+^ ions or pure novel [Co(CO)~2~(NO)~2~]^+^ salts, respectively. This is a promising route to other new metal carbonyl nitrosyl cations or even homoleptic metal nitrosyl cations. All compounds were characterized by vibrational spectroscopy and by single‐crystal X‐ray diffraction.