Molybdenum-catalysed reactions allylation

In a related study Hallberg el al. also investigated molybdenum-catalysed allylic alkylations in solution and on solid phase33 demonstrating that microwave irradiation could also be applied to highly enantioselective reactions (Scheme 7.13). 

The pro-nucleophile (5-H -oxazol-4-ones) was first reported by Trost and coworkers as nucleophile for a molybdenum-catalysed allylation. The direct asymmetric aldol reaction of Masaki and coworkers has an atom economy of 69.8% (Scheme 23.4, due to the loss of HNEtj acetate salt during the acetylation) and an E-factor of 13.1. If the synthesis of catalyst is considered. 

The use of molybdenum catalysts for allylic alkylation has been reported, and can be considered as complementary to the palladium-catalysed reactions. ... 

The two diasteromeric allyliridium-phosphoramidite complexes formed in the allylic 5 2 substitution of /-substituted allylic acetates, benzoates, or carbonates, with amine nucleophiles have been synthesized and characterized by NMR and X-ray diffractions. Kinetic and stereochemical studies using deuterated substrates indicate that the reaction, which occurs with a retention of configuration, proceeds by the mechanism in Scheme 3. This iridium-catalysed reaction is compared to molybdenum- and palladium-catalysed reactions. 

Molybdenum, tris(phenylenedithio)-structure, 1,63 Molybdenum alkoxides physical properties, 2,346 synthesis, 2,339 Molybdenum blue liquid-liquid extraction, 1,548 Molybdenum cofactor, 6,657 Molybdenum complexes acrylonitrile, 2,263 alkoxides, 3,1307 alkoxy carbonyl reactions, 2,355 alkyl, 3,1307 alkyl alkoxy reactions, 2,358 alkyl peroxides oxidation catalyses, 6,342 allyl, 3,1306... 

Several years ago transition metal mediated reactions in the area of C-glycoside synthesis were primarily limited to palladium and to a lesser extent nickel and manganese. Over the last few years several other metals, including chromium, molybdenum, tungsten, cobalt, and rhodium, have been utilized in C-glycoside synthesis. This section discusses the chemistry of palladium, which is divided into Stille-type couplings and 7T-allyl complexes. This is followed by considerations of the chemistry of chromium and the above-listed metals. A review by Frappa and Sinou entitled Transition Metal Catalysed Fimctionalization at the Anomeric Center of Carbohydrates appeared in early 1997 [55]. 

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