Diethyl benzylidene malonate

An eight-stage synthesis of 2-methylbenzomorphan (115) from benzal-dehyde via diethyl benzylidene malonate (110) in 19% overall yield has been reported<52) (Scheme 4,17). The amino radical precursor, N-chloramine (111),... 

The synthesis of the right-wing sector, compound 4, commences with the prochiral diol 26 (see Scheme 4). The latter substance is known and can be conveniently prepared in two steps from diethyl malonate via C-allylation, followed by reduction of the two ethoxy-carbonyl functions. Exposure of 26 to benzaldehyde and a catalytic amount of camphorsulfonic acid (CSA) under dehydrating conditions accomplishes the simultaneous protection of both hydroxyl groups in the form of a benzylidene acetal (see intermediate 32, Scheme 4). Interestingly, when benzylidene acetal 32 is treated with lithium aluminum hydride and aluminum trichloride (1 4) in ether at 25 °C, a Lewis acid induced reduction takes place to give... 

The activated Ba(OH)2 catalyst was successfully used for the Michael reactions of chalcone with active methylene compounds 290), as well as for the Michael reaction of other benzylidene derivatives of acetone, butanone, 3-methylbutanone, 4-methyl-2-pentanone, and 3,3-dimethylbutanone with ethyl acetoacetate and diethyl malonate. The reaction with diethyl malonate gave good yields of the Michael adduct (between 65 and 93%), whereas with ethyl acetoacetate various products were obtained, depending on temperature and amount of catalyst (Scheme 43) 291). Thus, by varying the reaction conditions, it was possible to obtain a single product with practically 100% selectivity, the yields being higher than those obtained with soluble catalysts, such as KOH, NaOH, or piperidine. 

The benzylidene complex [Ru=CHPh(Cl)(Bp)(CgHi4)(PCy3)], octahedral, exhibits an agostic Ru H-C interaction and displays catalytic activity for the ring closing metathesis of diethyl-malonate in the presence of CuCl as a cocatalyst in refluxing toluene.27 The crystal structure of the octahedral hydrido compound [Rn(Bp)(H)(C0)(AsPh3)2]-H20 has been reported.28... 

A mixture of diethyl malonate, NaH, and benzene refluxed 0.5 hr., cooled, methyl 2,3-anhydro-4,6-0-benzylidene- -D-alIopyranoside added, then stirred and refluxed 13 hrs. under Ng methyl 4,6-0-benzylidene-2-deoxy-2-dicarboxymethyl-a-D altropyranoside 7-lactone ethyl ester. Y 74%. F. e. s. S. Hanessian and P. Dex-traze. Can. J. Chem. 50, 226 (1972). 

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