Replacement of One CO Unit in Dicarbonyl(η5-cyclopentadienyl)cobalt Derivatives by Bis(tert-butylsulfonyl)acetylene

The broad diversity of CpCo(I) complexes

“…However, the first isolated monoalkyne compound was described by Krebs and colleagues, who reacted [CpCo(CO) 2 ] (2) with 3,3,6,6-tetramethyl-1-thiacycloheptyne generating 115 (Scheme 29) (Krebs and Wilke 1983). Later on, the simple replacement of one CO ligand in [CpCo(CO) 2 ] (2) with bis(t-butylsulfonyl)acetylene (BTSA) was achieved by stirring a 1:2 mixture of complex and alkyne in dichloromethane for 3 days followed by the investigation of the reactivity of 116 toward several reagents (Benisch et al 1998, Werz et al 2004, Goswami et al 2005.…”

Photolysis of dicarbonyl(cyclopentadiene)rhodium complexes with a pendent alkyne unit

“…It was identified by mass spectrometry and shows a strong IR band at 1963 cm À1 . Similar intermediates with an alkyne unit bound to a CpM(CO) n fragment are reported in the literature for M = Co, n = 1 [6,7], and M = Mn, n = 2 [8,9]. Also complexes of the type ArCr(CO) 2 (alkyne) have been reported [8,[10][11][12].…”

“…Dicarbonyl-g 5 -[1-(5,5-dimethylhex-3-ynyl)-3-phenylcyclopentadienyl]rhodium(I) (7)Reaction mixture in the first reaction step: Cyclopentenone 10 (816 mg, 4.86 mmol) in THF (10 ml), phenyllithium (20% in n-Bu 2 O, 2.00 g, 4.76 mmol). Reaction mixture in the second reaction step: Cyclopentadiene 13 in THF (25 ml), n-butyllithium (1 6. M in hexanes, 2.68 ml, 4.29 mmol), dicarbonylchlororhodium(I)dimer (500 mg, 1.29 mmol) in THF (100 ml).…”

Donor-substituted CpCo-stabilized cyclobutadienes and superphanes

“…To get a deeper insight into the mechanism several intermediates were isolated and characterized crystallographically. Mono(alkyne)cobalt complexes could be obtained as stable compounds by using either a highly strained [9] or a very electron-deficient alkyne such as bis(tert-butylsulfonyl)acetylene (BTSA) [10]. Cobaltols of type D with a further ligand L could also be characterized by means of X-ray analyses [11].…”