54966-76-6Relevant academic research and scientific papers
Reaktionen von Triorganylstannyldiazoessigsaeureestern mit Brompentacarbonylmangan
Kandler, Helmut,Bosch, Henry William,Shklover, Valery,Berke, Heinz
, p. 233 - 241 (2007/10/02)
Manganese pentacarbonyl bromide reacts with 2 equivalents of alkyl triorganylstannyldiazoacetates 1a-d to form the tetracarbonyl-μ(C,O)(1,2-alkoxycarbonyl-2-triorganylstannylethen-1-yl)manganese compounds 2a-d, presumably via the carbyne intermediate 3.Co
Flash photolysis studies of the reactions of dinuclear manganese carbonyl compounds with tributyltin hydride and triethylsilane
Sullivan, Richard J.,Brown, Theodore L.
, p. 9162 - 9169 (2007/10/02)
The reactions of Mn2(CO)8L2 (L = CO, PMe3, P(n-Bu)3, P(i-Bu)3, P(i-Pr)3, P(C6H11)3) with HSnBu3 and of Mn2(CO)10 with HSiEt3 were studied via flash photolysis, employing a conventional xenon flash lamp apparatus. The flash photolysis results are consistent with the conclusions based on continuous photolysis studies. The predominant reaction involves oxidative addition of the hydride to manganese at the site of CO loss. The rate of oxidative addition decreases as the steric requirements of L increase. Following oxidative addition, reductive elimination occurs. For HSnBu3, HMn(CO)4L and Bu3SnMn(CO)3L are formed. In the reaction of HSiEt3 with Mn2(CO)10, reformation of HSiEt3 dominates over formation of HMn(CO)5. The lifetime of the intermediate product resulting from the initial addition varies greatly with L. For small L. such as CO or PMe3, the intermediate persists for several seconds. With increasing size of L the addition process is slowed and the rate of elimination increases. A complete model for the reaction systems takes account of the semibridging form of the CO-loss product as the prevalent species in a noncoordinating solvent. Detailed modeling of the reaction system indicates that the on-off equilibrium involving coordination of the semibridging CO to the vacant manganese site is kinetically important. Formation of the semibridging form from the open form appears to have a significant energy barrier.
Photochemical reaction of dinuclear manganese carbonyl compounds with tributyltin hydride and with silanes
Sullivan, Richard J.,Brown, Theodore L.
, p. 9155 - 9161 (2007/10/02)
The photochemical reactions of Mn2(CO)8L2 (L = CO, PMe3, P(n-Bu)3, P(i-Pr)3) with HSnBu3 or HSiEt3 in hexane solutions have been studied, using 366- or 313-nm irradiation, and under CO or Ar atmospheres. Under CO, 1.1-3.7 atm, the products of the reaction of Mn2(CO)10 with HSnBu3 are HMn(CO)5 and Bu3SnMn(CO)5. Under Ar or low CO pressures, a third product, assigned as HMn(CO)4(SnBu3)2, is formed at the expense of Bu3SnMn(CO)5. For a given photon flux, the reaction rate is inversely related to [CO]. The behavior of the system is consistent with a reaction pathway that involves oxidative addition of the hydride to the coordinatively unsaturated metal center formed upon CO loss. Analogous results are observed for the phosphine-substituted manganese carbonyl dinners. Reaction with HSiEt3 proceeds much more slowly under equivalent conditions of irradiation. In the reaction with Mn2(CO)5, only HMn(CO)5 is seen as a significant product, with trace amounts of Et3SiMn(CO)5 also observed. These results are also consistent with oxidative addition to the Co-loss product as the only pathway for the photochemical reaction. None of the manganese dimers undergo photochemical reaction with either fluorene or triphenylmethane, in spite of the comparatively low C-H bond energy in each case.
Reaction of acetyl complexes with HMR3 (M = Si, Sn). Mechanism of acetaldehyde formation
Wegman
, p. 707 - 711 (2008/10/08)
The thermal reaction of the acyl complexes CH3C(O)M(CO)xL (M = Co, Mn; L = PPh3) with HM′R3 (M′ = Si, Sn; R = Bu, Ph) results in the formation of acetaldehyde and R3M′M(CO)xL. The rate law for the reaction is consistent with a pathway involving initial CO dissociation from CH3C(O)M(CO)xL, oxidative addition of the H-M′ bond, and reductive elimination of acetaldehyde. With HSnR3 the rate-determining step is CO dissociation from CH3C(O)M(CO)xL. In the case of HSiR3 the rate-determining step is oxidative addition of the H-Si bond.
