Bridged base

A review13 with 53 references of the transition-metal mediated supramolecular self-assembly is presented. Focus is on the self-assembly of macrocycles, catenanes, and cages from (en)Pd(N03)2 and pyridine-based bridging ligands. 

The reaction of 38 with nucleophiles gave a dinuclear species 39 in which each copper center is bonded to three C=C units, in contrast with the usual two-alkynyl-based bridge observed in many dinuclear alkynylcoppers.18 This... 

A boron to which is attached a Lewis base is isoelectronic with carbon and thus the Lewis base-bridge hydrogen feature in VII-N6 is undesirable. After the rearrangement the Lewis base is not on the apex (VI -N6), i.e., since it is isoelectronic with carbon it prefers the four-coordinate base site and thus becomes isoelectronic with IV-N6. 

Hemispherands (11) are by nature only partially preorganized for complexation, depending on their structural characteristics.30 129 132 Addition of hydrocarbon-based bridges, which essentially converts the monocycles to bicyclic systems, serves to provide a more rigid structural framework as in the cryptands.132... 

Relative to 7)/ for hole transfer through a single staggered alkane chain, norbornane-based bridges, characterized by two parallel alkane chains (relays linked by single... 

Norbornane-based bridge (two cross-linked alkane chain relays). 

A triazole ligand, (28), leads to asymmetric coordination modes, giving inequivalent metal centers in homobimetallic complexes.94 Complexes of Ru,Os exhibit efficient energy transfer mediated by the triazole ring. Benzimidazole-based bridging ligands like 2,2 -bibenzimidazolate... 

Explanation of the dramatic effects on physical properties of perfluorinated bridges in contrast with hydrocarbon-based bridges probably lies in the larger van der Waals radius (147 pm compared with 120 pm for hydrogen, i.e. fluorine is 23% larger than hydrogen) and the low polarizability of fluorine. Molecular... 

Christopher Ahlberg, Visual exploration of HTS data bases bridging the gap between chemistry and... 

Cinnamycin, a peptide antibiotic (Mr 2042 Da) produced by several Strep-tomyces strains including Streptomyces cinnamoneus cinnamoneus DSM 40005. Cinnamycin is a member of the Type B lantibiotics. It is characterized by a threefold thioether-based bridging pattern containing an additional lysinoalanine bridge connecting the C-terminus with... 

Fig. 4. A view of the F2((i-0)FF H2O molecule showing the urea based bridge and the water hydrogen bonded to the [i-oxo ligand and the urea bridge. Reproduced with permission from Ref. 45...

A connectivity of 1 is given for side chain metal-containing polymers as 1 in which the metal complex is connected via one bond to the main chain [11]. Additional examples for other connectivities are (Fig. 1-8) connectivity 2 in metal(yne)s 2 [12] connectivity 3 in arsenic(III) sulfide 3 connectivity 4 in a polymeric methyl rhenium oxide of the formula Ho.5[(CH3)o.92Re03] co 4 [13] or polymeric phthalocyanines 5 [14] connectivity 8 in lanthanide complexes of bis(tetradendate) Schiff base bridging ligands 6 [15]. 

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