The reaction of Ru 3(CO) 12 with 1,4-dichloro-but-2-yne in basic methanolic solution. Synthesis and crystal structure of (μ-H) 2Ru 3(CO) 9{μ 3-η 2-[H 2C [dbnd]C(H)C [tbnd]CC( [dbnd]O)OCH 3

Abstract

The title complex is obtained by reacting Ru 3(CO) 12 with 1,4-dichloro-but-2-yne (ClCH 2C CCH 2Cl, DCB) in CH 3OH/KOH solution (followed by acidification with HCl). The X-ray structure analysis shows that (μ-H) 2Ru 3(CO) 9{μ 3-η 2-[H 2C C(H)CCC( O)OCH 3]} complex contains a “parallel” ene-yne acetyl substituent, H 2C C(H)C CC( O)OCH 3; the formation of such a ligand starting from DCB is – to our knowledge – unprecedented. The synthesis of complex (μ-H) 2Ru 3(CO) 9{μ 3-η 2-[H 2C C(H)CCC( O)OCH 3]} occurs through the activation of CO and methanol. This process has been found for other reactions of functionalized alkynes with M 3(CO) 12 carbonyls (M = Fe, Ru) under basic methanolic conditions. The known hydridic cluster, (μ-H)Ru 3(CO) 9[μ 3-η 3-(MeCCHCH)] has been identified as the minor reaction product.