Cycloheptatriene complexes tungsten

At present, there are only NMR data available for 7r-arene and TT-cycloheptatriene complexes of chromium, molybdenum, and tungsten (80,158,161) (see Table XXV). The chemical shifts of the complexed... 

Later on, it was demonstrated that these heterocycles can undergo Diels-Alder reactions in the presence of an electrophile (Ss or Mel) and dienophiles <2002T1573, 2003HAC560>. These phosphoms-containing heterocycles were found to produce, upon reaction with tricarbonyl(cycloheptatriene)molybdenum(0) or tricarbonyl(mesitylene) tungsten(O), cr-complexes of the type L2M(CO)4 or I,(M(CO)( instead of 7t-complexes <1998EJI1079>. Some derivatives of this heterocycle were also found to display remarkable antibacterial activity <2005BML937>. 

As described in many reviews, Trost and his co-workers have carried out a pioneering work on the molybdenum-and tungsten-catalyzed allylic alkylation of allylic esters regioselectivity of the reaction is often complementary to the palladium-catalyzed allylic alkylation. The first asymmetric version was disclosed by Pfaltz and Lloyd-Jones in 1995 (Equation (63)). They used a catalytic amount of a novel tungsten complex, prepared from [W(CO)3(MeCN)3] or [W(cycloheptatriene) (COIs] and optically active (diphenylphosphino)phenyloxazolines 57, for the allylic alkylation of 3-aryl-2-propenyl phosphate with dimethyl sodiomalonate to isolate the corresponding branched alkylated compounds as a major isomer with an excellent enantioselectivity (96% ee). Unexpectedly, 3-aryl-2-propenyl carbonates are shown to be unreactive. It is worth noting that an isostructural molybdenum complex does not promote the catalytic alkylation under the same reaction conditions. In contrast, Lloyd-Jones and Lehmann reported the stereocontrolled... 

Diene complexes of the type [W(CO)4(diene)l (VI M = W) are formed by cyclo-octa-1,5-diene (79, 151), hexa-1,5-diene (151), and dimethyldi-vinylsilane (158) on heating with tungsten hexacarbonyl. Cycloheptatriene (158) displaces cyclo-octa-1,5-diene and 1 mol. of carbon monoxide from its tungsten complex ... 

Cycloheptatrienes with chromium, 5, 337 in molybdenum carbonyls, 5, 480 tj7-Cycloheptatrienyl complexes, with tungsten carbonyls and isocyanides, 5, 693 Cycloheptatrienyl compounds actinide complexes, 4, 227 with actinides, 4, 226 lanthanide complexes, 4, 122... 

Bis[dw-butyLphosphano] tellurium replaces norbornadiene, cycloheptatriene, acetonitrile, and dimethyl(methylene)oxosulfurane in chromium, molybdenum, and tungsten complexes. The P —Te compound acts as a bidentate ligand with the two phosphorus atoms coordinated to the metal atom1. The tetracarbonylchromium complex [R = CH(CH3)J can be recrystallized without loss of tellurium2. 

Ph3P=NH acts as a neutral donor, displacing carbonyl and other ligands from molybdenum and tungsten complexes. Thus m-[(Ph3P NH)2M ( 0)4] (M = Mo, W) and [(Ph3P NFl)2Mo(CO)3]2 were obtained from the hexacarbonyls, [(cycloheptatriene)Mo(CO)3], or [(C4pIjNCN)2Mo(CO)4]... 

Cobaltaie(l -), dodecacarbonylirontri-, tetraethylammonium, 27 188 Cobaltate(l -), dodecacarbonylirontri-, (triphenylphosphine)gold(l -(-), 27 188 -------, dodecacarbonylrutheniumtri-, tetraethylammonium, 26 358 Copper, (acetonitrile)dodecacarbonyltrico-balt ruthenium-, 26 359 Crystal growth, 26 377 Cyanate, tungsten complex, 26 42 Cycloheptatriene, molybdenum complex, 27 4... 

The reaction between PySeSePy (2,2 -dipyridyl diselenide) and [W(C7H8)(CO)4] (CvHg = norbornadiene) yielded the seven-coordinate complex [Wn CsI I4N(2-Se)-A-,SV 2(CO) ,].2 Oxidative addition of 2,2 -pyridine disulfide to [L3W(CO)3] (L3 = (pyridine)3, cycloheptatriene) in dichloromethane gave the seven-coordinate [W( 72-mp)2(CO)3] (mpH = 2-mercaptopyridine). This complex reacted with NO in the presence of additional pyridine disulfide to yield the seven-coordinate tungsten I) nitrosyl complex [Wn( 72-mp)3(NO)], as well as [W(rf-mp) 2 (N O) 2] and a trace amount of [Wiv(f72-mp)4].208... 

C7Hg02S, Benzenesulfonic add, 4-methyl-, rhodium complex, 27 292 C7H, Cycloheptatriene, tungsten complex, 27 4... 

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