By addition of acetyl

In liver mitochondria, palmitic acid, as its CoA ester, is lengthened by successive additions of acetyl CoA. There is also a liver microsomal enzyme capable of elongating saturated and unsaturated fatty acids by addition of acetyl CoA or malonyl CoA. 

This transmetallation has been used to obtain novel a-acetoxyalkylcopper/zinc reagents such as 1 from a-bromoalkyl acetates, obtained by addition of acetyl bromide to aldehydes.2... 

Table 5. //-Nitro Acetates Prepared by Addition of Acetyl Nitrate...

Dehydration of the aldol products of a Refoimatsky reaction does not normally occur under the usual reaction conditions but is often accomplished in a separate step to prepare unsaturated esters. Acid-promoted dehydration of -hydroxy esters can give significant amounts of nonconjugated unsaturated esters by either kinetic or thermodynamic control. Mirrington and cowoikers found that acetates can be prepared directly from Refoimatsky reaction mixtures by addition of acetyl chloride. Base-promoted elimination of the acetates produced conjugated esters in high yield. For the reaction shown in Scheme 14, the thermodynamic ratio of products (32) (33) is 40 60 and four different acid-promoted dehydration procedures gave at best a 68 32 ratio of products. ... 

Esterification is easily accomplished by any of the standard techniques. Falick and Maltby have produced a v ariety of esters by addition of 5 ml of the dry alcohol, rendered 0.2 M in HCl by addition of acetyl chloride, to the dry peptide and heating the reaction mixture at 45 °C for 1 h. Naylor et at. produced isopropyl esters of peptides by dissolving the peptide in 2-propanol/HCl... 

AcetyIonium hexachloroantimonate prepared by addition of acetyl chloride to a soln. of SbCls in chloroform and stirring at 0-5° for 45 min. dissolved in nitromethane, 3 g. 9a-fluoro-JLpregnene-ll, 17 a,21-triol-3,20-dione 21-acetate-benzene complex added, and allowed to stand 3 hrs. at 0-5° 2.5 g. 9a-fluoro-... 

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