Cationic half-sandwich Ru(II) complexes bearing (S)-2-pyridyl-imino-[2.2]paracyclophane ligands: Synthesis, intramolecular and interionic structure

Synthesis and structural chemistry of arene-ruthenium half-sandwich complexes bearing an oxazolinyl–carbene ligand

“…Both compounds were therefore isolated in enantio-and diastereomerically pure form. We note that several related ruthenium (g 6 -p-cymene) complexes with bidentate PN or NN [21] donor ligands have been reported, however, in these cases mixtures of two diastereomers were obtained [22]. Complexes of chiral imidazolylidene ligands with a stereogenic center at the metal atom have been previously prepared by Enders et al and in these particular cases, a mixture of diastereoisomers was observed [23].…”

The synthesis of substituted amino[2.2]paracyclophanes

“…33,50,51 Exploiting the transannular effect, the pseudo-gem aldehyde 13 17 could be prepared by directed Rieche formylation of ester 12 (Scheme 3). 52 Oxime (14) formation followed by the oxidation-rearrangement sequence gave the desired amine 15 in moderate to good yield. Key to reproducibility is the use of finely ground and dry reagents; if these precautions are not taken the reaction can stall after the oxidation, furnishing the hydroxamic acid instead of the amine.…”

“…The combined organic layers were washed with a sat. (14). To a mixture of hydroxylamine hydrochloride (0.208 g, 3.0 mmol, 3.0 eq.)…”

“…While moderate to high yields have been reported these require very precise reaction times and conditions. 8,12,13 More common routes to aminoparacyclophanes include the Curtius rearrangement of the appropriate carboxylic acid 9,14,[15][16][17][18] or the electrophilic amination of bromoparacyclophanes. Advantages of the former strategy include facile resolution of the acid 12,19 and the ability of acids to direct functionalisation of paracyclophanes.…”

Cationic half-sandwich quinolinophaneoxazoline-based (η6-p-cymene)ruthenium(ii) complexes exhibiting different chirality types: synthesis and structural determination by complementary spectroscopic methods

“…To the best of our knowledge, the only example of a cationic half-sandwich ruthenium(II)arene complex involving a [2.2]paracyclophane-derived N,Nligand was previously reported by us. 11 The lack of information about chiral N,N-chelate ruthenium complexes with chiral N,Nbidentate ligands and our constant interest in the synthesis of new chiral [2]paracyclo [2](5,8)quinolinophane derivatives 12 prompted us to perform a structural investigation of new asymmetric ruthenium complexes involving nitrogen-donor ligands exhibiting different types of chirality.…”