Tricarbonyl Derivatives of Manganese(I) with Diphosphinite Chelating Ligands

Abstract

Reaction of [MnBr(CO) 3 L] [L ϭ Ph 2 POCH 2 CH 2 OPPh 2 , L 1 , {(CH 3 ) 2 CH} 2 POCH 2 CH 2 OP{CH(CH 3 ) 2 } 2 , L 2 ] with AgO 3 SCF 3 and AgO 2 CCF 3 in dichloromethane afforded the new complexes [Mn(O 3 SCF 3 )(CO) 3 L] and [Mn(O 2 CCF 3 )(CO) 3 L], respectively. Substitution of O 3 SCF 3 resulted in the new species [Mn(SCN)(CO) 3 L], [Mn(NCCH 3 )(CO) 3 L](O 3 SCF 3 ) and, in the case of L 2 , [Mn(CN)(CO) 3 L 2 ]. By contrast, any attempt to displace the O 2 CCF 3 ligand in the same way was unsuccessful. After maintaining for some days the complex [Mn(CH 3 CN)(CO) 3 L 1 ](O 3 SCF 3 ) in dichloromethane at room temperature, the new complex [MnCl(CO) 3 L 1 ] was formed. All the new complexes were characterized by elemental analysis, mass spectrometry and IR and NMR ], together with the previously synthesized complex [MnBr(CO) 3 L 2 ], suitable crystals for X-ray structural analysis were isolated. In all of them the Mn atom adopts six-coordination by bonding to the three CO ligands, the two P atoms of L and either one C atom (CN), one oxygen atom (O 2 CCF 3 , O 3 SCF 3 ), one N atom (CH 3 CN, SCN) or the halogen atom (Cl, Br).

New Dinuclear Face‐ and Edge‐Sharing Bioctahedral Ruthenium Compounds Containing 1,2‐Bis(diphenylphosphanyloxy)ethane

“…This arrangement stabilises, in spite of the strain, a ruthena-phospha-oxa-cyclobutane ring. As the only source of CO is the bis(phosphinite) L ligand, and we did not observe similar behaviour for L with other metals, [18] these fragments must come from a metal-promoted disruption of the bidentate ligand. Moreover, although the yields are low, the reaction is perfectly reproducible.…”

“…[17] This is probably not the situation in our case because we did not observe such a process in reactions between the same ligand and other metals such as Re and Mn. [18] Other authors have observed the same product (POP) and suggested a P-P(O) to P-O-P thermal rearrangement prior to metal coordination, [19] a process that is favoured when R groups bonded to P are inductively electron-withdrawing groups like OR groups (as in our case). A likely mechanism involves partial hydrolysis of the ligand due to the prolonged heating and the presence of adventitious moisture, followed by a tautomeric rearrangement from the P-P(O) to the P-O-P form.…”

Protecting-Group-Free Site-Selective Reactions in a Metal–Organic Framework Reaction Vessel

“…We also examined 1•[Mn(CO)3(H2O)]Br by IR spectroscopy, which revealed characteristic CO stretches at 1951, 2040 and 1921 cm -1 . [35][36][37] Additionally, the phase purity of 1•[Mn(CO)3(H2O)]Br was confirmed by PXRD analysis (SI Figure S6.3).…”

“…Quantitative metalation was confirmed by energy-dispersive X-ray (EDX) analysis, which yielded an Mn:Br ratio of 4:1. We also examined 1 ·[Mn­(CO) 3 (H 2 O)]Br by IR spectroscopy, which revealed characteristic CO stretches at 1951, 2040, and 1921 cm –1 . − Additionally, the phase purity of 1 ·[Mn­(CO) 3 (H 2 O)]Br was confirmed by PXRD analysis (SI Figure S6.3).…”