Halogenoses, reaction with 2,4-dialkoxypyrimidines

Pliml, J., Prystas, M., The Hilbert-Johnson Reaction of 2,4-Dialkoxypyrimidines with Halogenoses, 8, 115. 

Heterodienophiles, new, heterocyclic synthesis using, 55, 1 Heteropentalenes, 69, 271 Hilbert-Johnson reaction of 2,4-dialkoxypyrimidines with halogenoses, 8, 115... 

The synthesis of cytidine9 by the Hilberb-Johnson procedure (which may be formulated as a reaction of 2,4-dialkoxypyrimidines with halogenoses) initiated further investigations in the field of the pyrimidine nucleoside synthesis. Thus, for example, the treatment of... 

Hilbert-Johnson reaction. Reaction of 2,4-dialkoxypyrimidines with halogenoses to yield pyrimidine nucleosides. 

The reaction of a 2,4-dialkoxypyrimidine with a halogenose (or an alkyl halide) has been assumed by Hilbert30 to proceed via a quaternary salt as intermediate. Thus, the stable l-methyl-2-methoxy-4-... 

The reactivity (in acetonitrile as solvent) of various 2,4-dialkoxy-pyrimidines19 towards 2,3,5-tri-O-benzoyl-D-ribofuranosyl chloride (59) was found to decrease in the order 2,4-dibenzyloxy-, 2,4-bis(p-methoxybenzyloxy)-, 2,4-dimethoxy-, 2,4-diethoxy-, 2,4-bis(2,4-di-methoxybenzyloxy), 2,4-diisopropoxypyrimidine. In all these cases, the j8 anomer represented the sole reaction product. In view of this stereospecificity, the reaction of the halogenose (59) with the above 2,4-dialkoxypyrimidines represents a procedure of choice for preparation of uridine or cytidine and their derivatives. When the Hilbert-... 

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