Alkanoic 2-bromo

The acetylsulfanyl alkanoic acids can also be prepared by thioacetylation of the corresponding bromo derivatives,[101 acrylic add derivatives, 1516 or lactones.133 A fluorescent sulfanylalkanoyl fluorescein derivative was prepared by reaction of acetylsulfanylalkanoyl amine with fluorescein isothiocyanate, followed by deprotection of the thiol group. 1 ... 

Angibaud, P, Chaumette, J L, Desmurs, J R, Duhamel, L, Pie, G, Valnot, J Y, Duhamel, P, Asymmetric synthesis of 2-chloro- and 2-bromo-alkanoic acids by halogenation of a-D-glucofuranose-derived silyl ketene acetals. Tetrahedron Asymmetry, 6, 1919-1932, 1995. 

Grignard reagents were formed with difficulty from both 5-bromo- and 5,5 -dibromo-2,2 -dithienylmethane they gave acids (71 and 81%, respectively) on carbonation.16 A carboxyl group attached to a thiophene ring has been decarboxylated with copper-quinoline (80%)39 bis(2-thienyl)alkanoic acids of general formula 83 decarboxylate quite readily on heating.40,107 In one case (83, R1 = Me R2 = H) the expected decarboxylation product was accompanied by a little of the dimer 84. 

N-Substitution of 1,2-Benzisothiazolin-3-ones. - Saccharin Na salt reacts with various bromoalkanes, bromoketones, and bromo-alkanoic acids (esters) to form N-substituted derivatives [35 ... 

Alkanoic acids, Fatty acids can be prepared by reaction of Grignard reagents and the chloromagnesium salts of cu-bromo acids (used because of solubility in THF) with Li2CuCl4 as catalyst (equation I). Usually some amounts of the diacid derived from the bromo acid are also formed. 

A general method has been worked out which allows the preparation of a number of butanediols-1,4 substituted in the 2,3-position (16,43). Starting materials are a-halo-genated (usually a-bromo) esters of alkanoic acids which can be condensed to 2,3-disubstituted succinate esters they are readily reduced with LiAlHij to the 2,3-disubsti-stituted butanediols-1,4 which are acetylated and then pyrolyzed at about 600°C. Dehydration of the butanediols-1,4 with KHSOi, on the other hand gives only 3,4-substituted tetrahydrofuran. 

---