Ferrocenophanes synthesis

Aza[3]ferrocenophanes, synthesis, 6, 187 Azaheterocycles, alkynylation with Ir catalysts, 7, 340 7-Azaindole, in trinuclear Ru and Os clusters, 6, 725 Azametallacyclobutane, tantalum complexes, 5, 168 Azametallacyclopropane, with niobium, 5, 87 Aza-oxo ligands, chromium complexes, 5, 353 Azaphosphirenes, with tungsten carbonyls, 5, 623 2H-Azaphosphirenes, with tungsten carbonyls, 5, 679 Aza-titanacyclopentenes, synthesis, 4, 407-408 Azavinylidenes... 

Diphosphaferrocene, with chromium carbonyls, 5, 220 l,l -Diphospha[2]ferrocenophane, synthesis, 6, 210 Diphosphazanes, in dinuclear Ru complexes, 6, 674 l,l -Diphosphetanylferrocenes, preparation, 6, 200-201 Diphosphine borane complex, polypyrrole support for,... 

Wang Z, Masson G, Peiris PC et al. (2007) Living photolytic ring-opening polymerization of amino-functionalizEd [l]ferrocenophanes synthesis and layer-by-layer self-assembly of weU-deflned water-soluble polyferrocenylsilane polyelectrolytes. Chem -A Eur J 13 9372-9383... 

A PEO macroinitiator with Si — H end groups was prepared through the condensation of monohydroxy-terminated PEO with CISiMePhH in the presence of pyridine [130]. The presence of the Si —Ph moiety prevents the hydrolysis of the Si — O — C bond, due to steric factors. This macroinitiator was subsequently used for the synthesis of poly(ferrocenyldimethylsilane), PFS, to afford PEO-fc-PFS block copolymers. The ROP of the ferrocenophane was conducted catalytically using the Pt(0) Karstedt s catalyst in toluene at 25 °C (Scheme 55). Rather broad molecular weight distributions (higher than 1.3) were obtained. 

In addition to the common methods of synthesis, it has been shown that the desulfurization of thioacetals yields organogermanes (Equations (7) and (8)) with excellent selectivity in some cases (Equation (9)).8 Ring-opening reactions of strained [l]ferrocenophanes furnish germanium-substituted ferrocenes9,10 (Equation (10)).9... 

The sequential addition method also allows the synthesis of many different block copolymers in which the two monomers have different functional groups, such as epoxide with lactone, lactide or cyclic anhydride, cyclic ether with 2-methyl-2-oxazoline, imine or episul-Hde, lactone with lactide or cyclic carbonate, cycloalkene with acetylene, and ferrocenophane with cyclosiloxane [Aida et al., 1985 Barakat et al., 2001 Dreyfuss and Dreyfuss, 1989 Farren et al., 1989 Inoue and Aida, 1989 Keul et al., 1988 Kobayashi et al., 1990a,b,c Massey et al., 1998 Yasuda et al., 1984]. 

Another impressive example is the facile cleavage of Si—C(Cp) bonds in strained [1]-ferrocenophanes with bridging silicon. This behaviour is the basis for the synthesis of high-molecular-weight poly(ferrocenylsilanes) (equation 47) and will be described in more detail in Section II.E.l. 

For this reason, tin containing ferrocenophanes are being investigated by Jurkschat and coworkers45. Their synthesis is given in Scheme 1045 and the structures of two of them are given in Figures 14 and 15. 

SCHEME 10. Synthesis of different tin containing ferrocenophanes. Reprinted with permission from Reference 45. Copyright 2000 American Chemical Society... 

Another topologically chiral K5 molecule is the chiral ferrocenophane ketone derivative 51 (Fig. 8), which is an intermediate in the synthesis of tetrabridged ferrocenophanes [79]. It is important to notice that in order to obtain a non-planar molecular graph, at least four of the ten Fe —C bonds must be taken into account. The K5 subgraph (52) also contains an oriented edge ( —CH2CH2CH2CO-fragment) and a coloured vertex (Fe atom). 

To date, the synthesis of strained [l]stannafeiTocenophanes as precursors for ROP is restricted to compounds with bulky substituents at tin. Previous attempts to prepare tin-bridged ferrocenophanes by the reaction of dilithioferrocene with diorganotin dichlorides, R2SnCl2, containing less bulky substituents (R = Me, Et, w-Bu, Ph) resulted in the isolation of oligomers (Mn < 4.6 x 10 ) and cyclic dimers . The crystal structure analyses of the [2]distannaferrocenophane 60 and the [3]tristannaferrocenophane 61, which are essentially unstrained, were also reported " . 

The first dibora[2] ferrocenophane (94) was prepared from l,L-dilithioferrocene and l,2-dichlorobis(dimefhylamino)di-borane. A dynamic process due to motion of the cyclopenfa-dienyl rings between staggered and eclipsed conformations was revealed by low-temperature NMR spectroscopy. A number of l,3-dibora[3]ferrocenophanes with B-E-B bridges (95 E=0, S, Se, Te, NR) were reported. Moreover, Wagner used diborylated ferrocenes for the synthesis of doubly bridged switchable ania-metallocenes (96) and (97), in which the bridges are created and... 

Scheme 5-43. Synthesis of l,3-dichalcogena-2-(/< /-/-butyl)pnicogena-[3]ferrocenophanes [224].

B. Synthesis, Properties, and Ring-Opening Polymerization of Silicon-Bridged 1 ]Ferrocenophanes... 

Gates DP (1997) The synthesis, structure, reactivity and polymerization behavior of boron- and sulfur-nitrogen-phosphorus heterocycles and highly strained chalcogen- and boron-bridged [1], ferrocenophanes. PhD thesis, University of Toronto... 

The synthesis of poly(ferrocenylene-vinylene) via ROMP of the vinylene-bridged [2]ferrocenophane 109 was reported in 1997 263 monomer was obtained from the McMurry coupling of l,l -ferrocenedicarbaldehyde. In the presence of a molybdenum ROMP catalyst, 109 was found to undergo polymerization (Scheme 11) to give an insoluble orange powder 110, which exhibited a conductivity of 10 S cm after iodine doping. Partially soluble block co-polymers 111 were also... 

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