Tert Butyl acetate

Common Name Prednisolone-21-tert-butyl acetate... 

Somfai and coworkers investigated the thermal isomerization of vinylaziridines 228 and found that while LDA-mediated isomerization of 228, possessing a tert-butyl acetate moiety (R2 = C02t-Bu), afforded tetrahydropyridines by aza-[2,3]-Wit-... 

In spite of their intrinsic synthetic potential, addition reactions of metal enolates of non-stabilized esters, amides, and ketones to epoxides are not widely used in the synthesis of complex molecules. Following the seminal work of Danishefsky [64], who introduced the use of Et2AlCl as an efficient catalyst for the reaction, Taylor obtained valuable spiro lactones through the addition reaction of the lithium eno-late of tert-butyl acetate to spiro-epoxides, upon treatment of the corresponding y-... 

The addition of lithium enolates to 2-alkoxyaldehydes occurs either in a completely non-stereoselective manner, or with moderate selectivity in favor of the product predicted by the Cram-Felkin-Anh model28 ( nonchelation control 3, see reference 28 for a survey of this type of addition to racemic aldehydes). Thus, a 1 1 mixture of the diastereomeric adducts results from the reaction of lithiated tert-butyl acetate and 2-benzyloxypropanal4,28. 

In the presence of a strong base, the ot carbon of a carboxylic ester can condense with the carbonyl carbon of an aldehyde or ketone to give a P-hydroxy ester, which may or may not be dehydrated to the a,P-unsaturated ester. This reaction is sometimes called the Claisen reaction,an unfortunate usage since that name is more firmly connected to 10-118. In a modem example of how the reaction is used, addition of tert-butyl acetate to LDA in hexane at -78°C gives the lithium salt of ferf-butyl acetate, " (12-21) an enolate anion. Subsequent reaction a ketone provides a simple rapid alternative to the Reformatsky reaction (16-31) as a means of preparing P-hydroxy erf-butyl esters. It is also possible for the a carbon of an aldehyde or ketone to add to the carbonyl carbon of a carboxylic ester, but this is a different reaction (10-119) involving nucleophilic substitution and not addition to a C=0 bond. It can, however, be a side reaction if the aldehyde or ketone has an a hydrogen. 

Successful results have been obtained (Renfrow and Chaney, 1946) with ethyl formate methyl, ethyl, n-propyl, iso-propyl, n-butyl, i o-butyl, sec.-butyl and iso-amyl acetates ethylenegl3rcol diacetate ethyl monochloro- and trichloro-scetates methyl, n-propyl, n-octyl and n-dodecyl propionates ethyl butyrate n-butyl and n-amyl valerates ethyl laurate ethyl lactate ethyl acetoacetate diethyl carbonate dimethyl and diethyl oxalates diethyl malonate diethyi adipate di-n-butyl tartrate ethyl phenylacetate methyl and ethyl benzoates methyl and ethyl salicylates diethyl and di-n-butyl phthalates. The method fails for vinyl acetate, tert.-butyl acetate, n-octadecyl propionate, ethyl and n-butyl stearate, phenyl, benzyl- and g aicol-acetate, methyl and ethyl cinnamate, diethyl sulphate and ethyl p-aminobenzoate. 

A practical a-heteroarylation of simple esters or amides has been developed via nucleophilic aromatic substitution. Exposure of chlorothiadiazoles 317 and 319 to NaHMDS and tert-butyl acetate or iV-dimethylacetamide leads to the formation of functionalized... 

Condensation reactions are conveniently written as carbanion reactions, and yet it is clear that the metallic cation is important too. For example, sodium and lithium give quite different results in the condensation of acetophenone and tert-butyl acetate.422 The various rate and equilibrium constants depend on the nature of the associated metal. Lithium, zinc, and magnesium, which give the aldol condens-... 

Ethyl tert-butyl malonate has been prepared by adding tert-butyl acetate and ethyl carbonate to sodium triphenylmethyl,3 and from ethyl malonyl chloride and fer/-butyl alcohol.4 The present procedure is an adaptation of that for the preparation of di-fer(-butyl malonate.2... 

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