Synthesis and characterization of MH⋯HOR dihydrogen bonded ruthenium and osmium complexes (η5-C5H4CH2OH)MH(PPh3)2 (M = Ru, Os)

Treatment of RuCl 2 (PPh 3 ) 3 with 6-dimethylaminopentafulvene in THF in the presence of water produced (η 5 -C 5 H 4 CHO) RuCl(PPh 3 ) 2 , which was reduced by NaBH 4 to give the Ru-H⋯HO dihydrogen bonded complex (η 5 -C 5 H 4 CH 2 OH) RuH(PPh 3 ) 2 . The dihydrogen bonded complex (η 5 -C 5 H 4 CH 2 OH)RuH(PPh 3 ) 2 could also be synthesized by the reduction of complex (η 5 -C 5 H 4 CHO)RuH(PPh 3 ) 2 , which was obtained by the reaction of RuHCl(PPh 3 ) 3 with 6-dimethylaminopentafulvene in the presence of water. The analogous dihydrogen bonded osmium complex (η 5 -C 5 H 4 CH 2 OH)OsH(PPh 3 ) 2 was similarly prepared. Single crystal structures and DFT calculations support the presence of intra-molecular H…H interaction, with separations of around 1.9 to 2.0 Å.