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XV. Researches on Acids of the Lactic Series. — No. I. Synthesis of Acids of the Lactic 

 Series. By E. Frankland, F.B.S., Professor of Chemistry in the Royal Institution 

 of Great Britain and in the Government School of Mines ; and B. F. Duppa, Esq. 



Received February 14, — Head March 1, 1866. 



With the exception of the acetic series, no family of organic acids has excited so much 

 interest amongst chemists, and been the subject of such numerous researches, as that 

 represented by lactic acid. Its character, intermediate between the monobasic and 

 dibasic acids, its close relations to the acetic and .acrylic families, and the numerous 

 important transformations which it undergoes, have all contributed to render this family 

 an attractive subject for experimental inquiry and a fruitful source of theoretical specu- 

 lation. These inquiries and hypotheses have contributed greatly to the elucidation of 

 the habits of these acids, and still more to the general progress of organic chemistry. 

 Nevertheless there are two circumstances which have materially interfered with their 

 complete success; these are, the comparatively small number of the known members 

 of this series, and the absence of any synthetical proof of the nature of their consti- 

 tuent radicals. These obstacles to a more satisfactory conception of the internal archi- 

 tecture of the acids in question we have endeavoured to remove by the production, 

 according to purely synthetical methods, of a number of new members of this series, a 

 brief notice of which we have from time to time had the honour of submitting to the 

 Royal Society *, and the more complete history of which we propose to develope in the 

 following pages. Our general method for synthetically producing the acids of the lactic 

 series depends upon the replacement of one of the atoms of dyad oxygen in oxalic acid, 

 or rather in the ethereal salts of oxalic acid, by two atoms of monad alcohol radicals. 

 Such a replacement at once transforms dibasic oxalic acid into a monobasic acid of the 

 lactic series. The nature of this transformation, as well as the relations of oxalic acid 

 to the lactic family, is clearly seen from the following comparison of the formulae of 

 oxalic acid and of its derivative, dimethoxalic acid : — 



c,-! 



[o 



OH jCOHo . ^ 



rCOHo 

 ICOHo''' 



[(CH3)2 



OH fCMe,Ho 



or 



fCM. 



Ico 



'2- 



O IC O Ho 



lOH 



lOH 



Oxalic acid. Dimethoxalic acid. 



This substitution of alcohol radicals for one atom of oxygen in oxalic acid can be 



• Proceedings of the Royal Society, vol. xii. p.396; vol.xiii. p.l40; vol.xiv. pp. 17, 79, 83, 191, 197, and 198. 

 t In this paper 0=16, C=12, H=l, Zn = 65, Ba=137, Cu=63-5, Ho=(OH) the monad radical hydroxy! 

 or peroxide of hydrogen, Eto = (OCjII,) ethoxyl or peroxide of ethyl, &c. 

 MDCCCLXVl. 2 U 



