2,3,4,7-Tetrahydro-1 H-inden-2-ol: synthesis, molecular structure and coordination chemistry

Abstract

2,3,4,7-Tetrahydro-1 H-inden-2-ol ( 1) has been synthesised by Birch reduction of indan-2-ol. A single-crystal X-ray structure analysis of 1 shows the compound to exist as hydrogen-bonded polymers along the c-axis due to the presence of a series of hydrogen-bonds between hydroxo functions. The ferrocene ester derivatives, ferrocene carboxylic acid 2,3,4,7-tetrahydro-1 H-inden-2-yl ester ( 2) and ferrocene carboxylic acid indan-2-yl ester ( 3) have been prepared by peptidic coupling of ferrocene carboxylic acid with 1 and with indan-2-ol, respectively. The single-crystal X-ray structure analyses of 2 and 3 reveal in both cases the cyclopentadienyl rings to adopt an eclipsed conformation with the indenyl substituent being rotated out of the Cp ester plane by almost 90°, allowing no efficient interaction between the π-system of the Cp ring and the indene moiety. The dienyl derivative 2 reacts with RuCl 3 · nH 2O in refluxing ethanol to afford [Ru(arene)Cl 2] 2 ( 4) (arene=ferrocene carboxylic acid indan-2-yl ester) as a mixture of isomers.