Fulvene Complexes

Methyl groups in the cobaltocenium ion are sufficiently acidic to be deprotonated by strong bases. The ensuing fulvene complexes are not isolated, but can be alkylated in situ with aUcyl iodide. Starting from pentamethylcobaltocenium, derivatives which bear five or 10 alkyl, benzyl, or other functionalized organic groups have been prepared (Scheme 29). ... 

The complexes [ReCp (CO)2X(NCMe)][BF4], prepared from the parent dihalides and AgBF4, react with Et3N 3HF to produce the fulvene complex [Re( -C5Me5CH2)X(CO)2] (see Section 9). ... 

Photolysis of ReCp (CO)3 in CeFe does not lead to the jj -CeFe complex. Instead, both C-H and C F activation take place leading inter alia to the fulvene complex Re(jj -C6Me5CH2)(CO)2(C6F5) and HF elimination (see Section 9). ... 

Kreiter and co-workers (68) studied the photochemistry of this phenyl complex in the presence of fulvenes and found that labile QHsMn-(CO)4(i7 -fulvene) complexes were formed [Eq. (83)]. These thermally... 

HMn(CO)s has been photolysed in Ar and CH4 matrices and this produces CO and HMn(CO)4, a compound having a C, structure. Narrow band photolysis also leads to small amounts of a second isomer of HMn(CO)4 which has a C4 structure. PhMn(CO)5 has been observed to photoreact with 6,6-dimethyl- and 6,6-diphenylfulvene to give Ph(CO)4Mn(T -fulvene) complexes. Irradiation of RMn(CO)jL2 [10 R = H or Me, L = P(OPh)j] and of MeMn(CO>4L in benzene induces formation of the orthometallated products (11). These arise by formation of a 16-electron intermediate which in-tramolecularly activates a C-H bond of Ph in PCOPha). ... 

Cp (C5Me4CH2CH2NMe2)TiCl2 (Cp = Cp, Cp ) are obtained by oxidation of the Ti(m) compounds Cp (C5Me4CH2CH2NMe2)TiCl with PbCl2. The molecular structure of the Cp derivative has been determined by X-ray diffraction, which reveals a non-coordinated NMe2 group. The dichloro compounds have been converted to a series of dialkyl, vinyl, titanacyclobutane, and fulvene complexes by the appropriate reactions (Scheme 531 Section 4.05.4.2.4).1093... 

The first dinuclear complex of a diborafulvene was reported by Herber-ich et al. (47). They reacted the 3,4-diboratafulvene derivative Li2[H2C(CHBNEt2)2] with [RhCl(COD)]2 and obtained the 3,4-dibora-fulvene complex 55. The complexes 53b and 55 are almost isostructural however, they have 32 and 30 VE, respectively. 

With various nitriles, two different hetero dinuclear complexes with arrangement (73) are obtained (equation 35). The formation of the cyclometalated species (79) involves a hydrogen transfer from a Cp methyl group to the electrophilic carbon center of the nitrile in an intermediate fulvene complex. Kinetic results indicate that a second molecule of nitrile catalyzes the conversion of this fulvene intermediate into (80). ... 

The UV-vis-near-IR absorption spectrum of the solution of the protonated polymer exhibits MLCT bands and valence tautomerization similar to those of 1,8-Fc2Aq as shown in Fig. 3.32, indicating the formation of fulvene complexes in the main chain in solution. Infrared spectrum of the protonated polymer also shows the similarity with that of l,8-Fc2Aq, namely, half the CC triple bond remains. 

Alkylation of the fulvene complex (TiCl3)2(li-il T 5-C oHg) wifli MgBz2].THF affords (TiBz3)2(p-... 

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