Ethyl lithioacetate

A biarylpropionic acid derivative containing a furan ring as a prominent feature has antiinflammatory activity. The patented synthesis involves a straightforward organometal1ic addition of ethyl lithioacetate to aldehyde 12 followed by saponification... 

Much less is known about aldol additions to chiral aldehydes that have heteroatoms other than oxygen at the a-stereocenter. In connection with a synthesis of statine analogs, a-amino aldehyde (176) was allowed to react with ethyl lithioacetate to obtain (177) and (178) in a ratio of 60 40 (equation 114). 

Ethyl-2-fluorobenzothiazolium tetra-fluoroborate, 223-225 Ethyl indolepropionates, 313-314 Ethyl ketals, 262 Ethyl lactate, 298 Ethyl lithioacetate, 225 Ethyl malonate, 311 Ethyl mandelate, 298 Ethyl mesityl ketone, 295 Ethyl methyl ketone, 340 N-Elhyl-5-phenylisoxazoiium 3 -sulfonate, 226... 

Ethyl lithioacetate, LiCH2COOC H6.,This reagent is prepared by metalation of ethyl acetate with LDA in THF at —78°. 

LACTONES Ethyl lithioacetate. Iron carbonyl. Lithioallyltrimethylsilane. Silver(I) trifluoroacetate. Triphenyl-phosphine-Diethyl azodicarboxylate. 

Related Reagents. t-Butyl Q -Lithiobis(trimethylsilylacetate Ethyl Lithioacetate Ethyl Lithio(trimethylsilyl)acetate Ethyl Trimethylsilylacetate Triethyl Phosphonoacetate Trimethylsilyl-... 

Related Reagents. f-Butyl a-Lithiobis(trimethylsilyl)acetate f-Butyl Trimethylsilylacetate Ethyl Bromozincacetate Ethyl Lithioacetate Ethyl Trimethylsilylacetate Ketene Bis(trimethyl-silyl) Acetal Ketene f-Butyldimethylsilyl Methyl Acetal l-Methoxy-2-trimethylsilyl-l-(trimethylsilyloxy)ethylene Methyl (Methyldiphenylsilyl)acetate Methyl 2-Trimethylsilyl-acrylate Triethyl Phosphonoacetate Trimethylsilylacetic Acid. 

Related Reagents. t-Butyl a-Lithiobis(lrimethylsilyl)acetate t-Butyl Trimethylsilylacetate Dilithioacetate Ethyl Bromozin-cacetate Ethyl Lithioacetate Ethyl Lithio(trimethylsilyl)acetate Ketene Bis(trimethylsilyl) Acetal Ketene t-Butyldimethylsilyl Methyl Acetal l-Methoxy-2-trimethylsilyl-l-(trimethylsilyloxy)-ethylene Methyl (Methyldiphenylsilyl)acetate Trimethylsilyl-acetic Acid. 

Related Reagents. t-Butyl a-Lithioisohutyrate Dilithio-acetate Ethyl Lithioacetate Ketene Bis(trunethylsilyl) Acetal Ketene f-Butyldimethylsilyl Methyl Acetal l-Methoxy-l-(tri-methylsilyloxy)propene l-Methoxy-2-trunethylsilyl-l-(tri-methylsilyloxy)ethylene Tris(trimethylsilyloxy)ethylene. 

Michael intramolecular alkylation. The reaction of f-butyl lithioacetate (1) with ethyl 6-iodo-2-hexenoate 2 in the presence of potassium t-butoxide in THF at - 78° results in a single trans-1,2-disubstituted cyclopentane (3). Reaction of 2 with f-butyl lithiopropionate (4) under the same conditions results mainly in syn-5, but when HMPT is also present anti-5 is mainly formed. Similar stereoselectivity is observed in reaction of 1 and 4 with ethyl 6-iodo-2-heptenoate in formation of... 

Few examples exist for the conjugate addition of ester enolates to a,(3-unsaturated esters typically the incipient enolate undergoes decomposition and secondary reactions. The first examples, described by Schlessinger,144 are the addition of /-butyl lithioacetate and /-butyl a-lithio-a-(methylthio)propionate to butenolide (176 Scheme 69). Similarly, Normant reported that cyclopropanes are obtained from a-ha-loesters (177) and ethyl acrylate or acrylonitrile.145... 

A Michael addition of the silyl enolate was employed in a short synthesis of ( )-methyl jasmonate from cyclopentenone (eqs 9 and 10). This convergent scheme was carried out in three steps conjugate addition of methyl Q -(methyldiphenylsilyl)lithioacetate to cyclopentenone, alkylation of the resulting enolate with (Z)-l-bromopent-2-ene, and desilylation with potassium fluoride ( )-ethyl jasmonate was prepared in a similar fashion. In the conjugate addition step, the Q -(methyldiphenylsilyl)ester gave superior results to those obtained with the a-trimethylsilyl esters. 

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