Metallacycloalkanes and -alkenes

Metallacyclopentadienes: structural features and coordination in transition metal complexes

“…The formation of metallacyclic fragments is observed in many reactions of organic substrates with transition metal complexes, for example, in cycloaddition, insertion of metal atoms into C7H bonds, reactions accompanied by dimerisation of unsaturated molecules through C7C coupling or reactions involving carbonyl, nitrile and other ligands of the starting complex. Methods for the synthesis of compounds containing metallacyclic fragments and their chemical properties were described in general reviews 1,2 as well as in reviews devoted to special problems. 3 ± 5 Transition metal complexes containing metallacyclic fragments play an important role in metal-catalysed chemical transformations, such as alkene and acetylene metathesis, isomerisation of strained rings, cycloaddition of alkenes, oligomerisation of dienes and polymerisation.…”

“…Coupling of alkenes or alkynes in the coordination sphere of metal atoms is widely used in the synthesis of metallacyclic compounds giving rise primarily to five-membered metallacycles. 1,2 Of particular interest are five-membered unsaturated metallacycles, the so-called metallacyclopentadienes (MCPs).…”

“…The structure of the uncoordinated MCP fragment has been discussed in detail earlier. 2,18 Hence, we do not consider mononuclear complexes. Complexes with metallacycles, in which one or several carbon atoms are replaced with heteroatoms (N, O, S, etc.…”

18‐, 20‐ und 22 gliedrige Dimetallaortho‐, ‐meta‐und ‐para[7.7]cyclophane ‐ die ersten typischen Metallaphane

“…9(4)], PI-Lil 258.4 (5) [252.1 (5)], Lil-C1 262.9 (6) [261. 9(6)], Lil-C15 260.1 (6) [270. 8(6)], Lil-C2 276.…”

“…2(6)]. Lil-01 197.0 (6) [189.6 (7)], Lil-02 199.2 (6) [195.4 (7)]; C1-P1-C15 90.6(1) [90. 4(1)], 01-Lil-02 100.8 (2) [I 10.1 (3)].…”