New insight into a convenient base-promoted synthesis of Ru₃(CO)₁₂

The reaction of Ru3(CO)12 with 1,4-dichloro-but-2-yne in basic methanolic solution. Synthesis and crystal structure of (μ-H)2Ru3(CO)9{μ3-η2-[H2CC(H)CCC(O)OCH3]}

“…A comparable reaction sequence was found for the allenylidene complex Fe 3 (CO) 9 (l-CO)[C@C@C(H)Ph] to give the allenyl ferrole-like Fe 2 (CO) 6 C(@O)OCH 3 ] (3a) where the CO presumably comes from the cluster and one hydrogen and the CH 3 O group from addition and splitting of methanol [18]. We have found that this is a general process; we could indeed obtain the ferrole-like Fe 2 (CO) 6 [H 2 CCC(H)C(@O)OCH 3 ] (3b) homologue of 3a by reacting Fe 3 (CO) 12 with propargyl alcohol or propargyl chloride in CH 3 OH/KOH solution. The acetyl-substituted ferrolic complexes 3 mentioned above and their allenylidene precursors are shown in Scheme 2.…”

“…We have previously found that the reaction of hex-1-en-3-yne [H 2 C@CHC"CEt] with Fe 3 (CO) 12 yields the ferrole-like Fe 2 (CO) 6 [(C 2 Et 2 )C(@O)O] carboxylato complex upon splitting of water into its three components favoured by the silica gel used for t.l.c. purification [17].…”

“…Another example involving DCB is given by the reactions with Fe 3 (CO) 12 both under thermal and alkalyne conditions to give the butatrienyl complex Fe 2 (CO) 6 [H 2 C@C@C@CH 2 ]. Somewhat related to this behaviour is the recently reported synthesis of Ru 3 (CO) 12 from [Ru(CO) 2 Cl 2 ] n in a reaction involving KOH and 2-ethoxyethanol, formation of formyl groups (WGSR reaction) and loss of chlorine [6].…”

“…Another example involving DCB is given by the reactions with Fe 3 (CO) 12 both under thermal and alkalyne conditions to give the butatrienyl complex Fe 2 (CO) 6 [H 2 C@C@C@CH 2 ]. Somewhat related to this behaviour is the recently reported synthesis of Ru 3 (CO) 12 from [Ru(CO) 2 Cl 2 ] n in a reaction involving KOH and 2-ethoxyethanol, formation of formyl groups (WGSR reaction) and loss of chlorine [6]. In contrast, uptake of HCl in the reaction of Ru 3 (CO) 12 with BUD in conditions comparable with those used in this work leads to the open cluster (l-Cl)Ru 3 -(CO) 9 [H 2 CCC(H)CH 2 ] (2c) [1b] discussed below.…”

“…We have also found that BUD and 1,4-dichloro-but-2-yne (DCB) react with Fe 3 (CO) 12 loosing, respectively, the OH or the chlorine substituents and forming the binuclear butatrienylic complex Fe 2 (CO) 6 [H 2 C@C@C @CH 2 ] [2]. This prompted us to explore the reactivity of DCB towards Ru 3 (CO) 12 for a comparison with the results already reported for BUD [1b].…”