The dianions from a variety of P-keto esters have been generated using 1 equiv of sodium hydride and 1 equiv of n-butyllithium or methyllithium or 2 equiv of lithium diisopropylamide. The dianions react with a range of alkylating agents to produce y-alkylated products exclusively in good yield. Reaction of these dianions with a,wdihaloalkanes yields cyclic 1 : 1 adducts, cyclic 1 : 2 adducts, or acyclic 1 : 2 adducts, depending on the alkylating agent and the reaction conditions. This method offers ready access to a wide range of compounds which were previously difficult to obtain, ecently we had envisioned the synthesis of a num-(4) J. D. Hagarty, U. S. Patent 3,565,928 (1971); Chem. Absrr., 74, ( 5 ) T. M. Harris and C.

A method for the successful acylation of the dianion of simple β-keto esters to yield β,δ-diketo esters has been developed. The dianion of methyl acetoacetate also reacts with the monoanion of methyl acetoacetate to give a triketo ester which cyclizes to methyl orsellinate. These dianions also add to nitriles to give 5-amino-3-keto-4-pentenoates which may in some cases cyclize to 4-hydroxypyridones.

It is discovered that hexamethyldisilazane, a reagent generally used to silylate amino, hydroxyl, sulfhydryl, and carbonyl groups, reacts with β-diketones to form their trimethylsilyl enol ethers in high yield.An efficient and simple procedure for aminating β-triketones to their enaminodiketones by the use of hexamethyldisilazane is also described.

The dianion of methyl acetoacetate reacts with ketones and aldehydes to yield δ -hydroxy-β-keto esters. These hydroxy esters can be dehydrated to the corresponding γ,δ-unsaturated-β-keto esters which are useful in annelation reactions to form cyclic β-keto esters. The dianion of methyl acetoacetate does not appear to undergo conjugate addition to simple α,β-unsaturated ketones, instead only carbonyl addition occurs.

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