Umsetzungen der lithiierten Halbsandwich-Komplexe (CO)3MC5H4-Li (M = Mn, Re) mit organischen Carbonylverbindungen

Article abstract of DOI:10.1016/0022-328X(95)05552-Z

The reactions of the lithiated half-sandwich complex (CO)3MnC5H4-Li (-Li, 2a) with derivatives of organic dicarboxylic acids have been investigated with the goal of introducing several cymantrenyl () substituents in close proximity into organic molecules.The carboxylic acid chlorides of terephthalic and fumaric acid give, after reaction with excess 2a in THF solution and chromatography of the primary lithium compounds on silica, the bis(dicymantrenylcarbinols), 2C(OH)-C6H4-C(OH)2 (13a) and E-2C(OH)-CH=CH-C(OH)2 (17a) which contain fourcymantrenyl units.Phthaloyl chloride produces a product with isobenzofuranol skeleton and three cymantrenyl substituents.Cyclic anhydrides such as maleic and phthalic anhydride lead to lactons containing two geminal cymantrenyl groups.With chloroformates, the lithiated derivatives of cymantrene and cyrhetrene, (CO)3MC5H4-Li (M = Mn (2a), Re (2b)) cab be directly converted to tris(cymantrenyl)- and tris(cyrhetrenyl) carbinol, 3C-OH (18a) and 3C-OH (18b), respectively.In the presence of paraformaldehyde complexes 2a,b are first converted into the hydroxymethyl compounds (CO)3MC5H4-CH2OH (M = Mn (21a), Re (21b)) which then react, by further lithiation and formaldehyde insertion steps, to give 1,2-bis(hydroxymethyl) half-sandwiches, (CO)3MC5H3(CH2OH)2 (M = Mn (22a), Re (22b)).Starting from thionyl chloride and 2a, dicymantrenyl sulfoxide, 2SO (28a), is obtained.The new complexes have been characterized on the basis of their 1H and 13C NMR data.Keywords: Manganese; Rhenium; Lithiated half-sandwich complexes; Cyclopentadienyl complexes