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The optically active (4S,8S)‐4, 8‐bis(hydroxymethyl)‐1,5,7‐triazabicyclo[4.4.0]dec‐5‐ene ((S,S)‐1) has been synthesized in nine steps from L‐asparagine with a total yield of 5.1%. Similarly, the enantiomer (R,R)‐1 has been prepared from D‐asparagine. (S,S)‐ and (S,S)‐1 are representative examples of rigid and functionalized bicyclic guanidine systems and constitute useful intermediates in the construction of chiral selective anion‐receptor molecules.

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Neutral ruthenium hydrides Ru(CO)ClH(L)(PPh3)2 bearing one N-donor ligand react with 1-alkynes at 23 °C to yield neutral alkenyl complexes Ru(CO)Cl(CHCHR)(L)(PPh3)2. Under similar conditions, cationic hydrido complexes [Ru(CO)H(L)2(PPh3)2]PF6 with pyridine-type N-donor ligands yield alkynyl complexes [Ru(CO)(CH≡CHR)(L)2(PPh3)2]PF6 as a result of the reaction of the intermediate labile alkenyl with a second molecule of alkyne. Under more forcing conditions, 1-alkynyl complexes could also be prepared from the neutral ruthenium hydrides. Cationic ruthenium hydrides with bidentate N-donor ligands are unreactive toward 1-alkynes. Neutral alkenyl complexes Ru(CO)Cl(CHCHR)(L)(PPh3)2 (R = p-MeC6H4, CMe3; L = pyridine, isoquinoline) reacted smoothly with 1-alkynes to afford the corresponding σ-alkynyl ruthenium derivatives Ru(CO)Cl(C≡CR)(L)(PPh3)2.