91 S-PF.] 



FORMIC ALDEHYDE 



173 



17, 321). Or from mannitol through 

 n-hexane (n-hexyl alcohol [23 ; B]), and 

 then as below under V. 



NOTE : Generators of n-hexane given under 

 n-hexyl alcohol thus become generators of 

 formic aldehyde. 



[T.] From malic acid [Vol. II]. 

 Crotonic aldehyde is among- the pro- 

 ducts of electrolysis of sodium malate 

 (v. Miller and Hofer, Ber. 27, 470), 

 and can be converted into crotonic acid, 

 &c., as under F and J. 



[U.] Dextrose [154] gives 'trioxy- 

 methylene' among the products of its 

 electrolysis in presence of dilute sul- 

 phuric acid (Renard, Ann. Chim. [5] 

 17, 321), and this is resolved into 

 formic aldehyde as under D. 



[V.] From n-propyl alcohol [15] 

 through propyl ether (Chancel, Ann. 

 151, 304 ; Linnemann, Ann. 161, 37 ; 

 Norton and Prescott, Am. Ch. Journ. 

 6, 243). The latter gives formic alde- 

 hyde (trace) by pyrogenic decomposi- 

 tion (Tistschenko, Journ. Russ. Soc. 

 31, 784; Ch. Centr. 1900, 1, 586). 



Or the alcohol gives formic aldehyde 

 (2-72 per cent.) by incomplete com- 

 bustion (Mulliken, Brown, and French, 

 Am. Ch. Journ. 25, in). 



Or from n-propyl alcohol through 

 n-hexane (n-hexyl alcohol [23 ; A]). 

 The latter when mixed with air and 

 passed over heated platinum gives 

 formic aldehyde (v. Stepski, Monats. 



23, 773> 



Or from normal or isopropyl alcohol 

 [16] through propylene, acrole'in [lOl] 

 (see under benzyl alcohol [54; E]), 

 acrylic, a-chlorlactic, and glyceric acids, 

 &c., as above under M. 



NOTE : All generators of propylene thus 

 become generators of formic aldehyde (see 

 under isopropyl alcohol [16] and under glycerol 

 [48] for generators of propylene). 



[W.] From acetal [93] through gly- 

 collic aldehyde (see under furfural 

 [126 ; P]), and then as above under O. 



[X.] From ucibutyl alcohol [18], being 

 among the products of slow combustion 

 of the vapour in contact with heated 

 platinum (v. Stepski, Monats. 23, 773). 



Or from tertiary butyl alcohol [19] by 

 incomplete combustion (5-17 per cent. : 



Mulliken, Brown, and French, Am. Ch. 

 Journ. 25, in), or by passing the 

 vapour mixed with air over a heated 

 platinum spiral, acetone being simul- 

 taneously formed (Trillat, Comp. Rend. 

 132, 1495). 



Or from this last alcohol and potassium 

 cyanide [172], the alcohol being con- 

 verted into tertiary butyl iodide and 

 cyanide, and the latter reduced to tri- 

 methylethylamine, the hydrochloride of 

 which gives tertiary amyl alcohol by 

 the action of silver nitrite (Tissier, 

 Ann. Chim. [6] 29, 335 ; Freund and 

 Lenze, Ber. 24, 2150). From tertiary 

 amyl alcohol as above under N". 



[Y.] From amyl alcohol [22] through 

 amylene (trimethylethylene) and tertiary 

 amyl alcohol (see under acetone [106 ; 

 E]), and then as above under ET. Formic 

 aldehyde (2-01 per cent.) is also formed 

 by the incomplete combustion of amyl- 

 ene (Mulliken, Brown, and French, 

 loc. cit.). 



[Z.] From choline [Vol. II] through 

 glycol [45] and glycollic aldehyde (as 

 under furfural [126 ; H ; K]), and then 

 as above under O. 



[AA.] From trimethylamine [Vol. II] 

 through methyl chloride (see under 

 methane [l; Z]). From the latter 

 through methylene chloride, methylal, 

 &c., as above under C. 



[BB.] From acrole'in [lOl] through 

 acrylic acid by oxidation, and from the 

 latter through a-chlorlactic, oxyacrylic 

 (gly cidic) , and glyceric acids to pyrorace- 

 mic, crotonic, and /3-methylglyceric acids 

 as above under D and M. 



[CC.] From crotonic aldehyde [102] 

 through crotonic to /3-methylglyceric 

 acid as above under M, H, and J. 



[DD.] From isobutyric and acetic 

 aldehydes [94 ; 92] through the aldol, 

 C 6 H 12 O 2 , trimethylethylene-lactic acid, 

 and tertiary amyl alcohol (see under 

 acetone [106 ; DD]). From the latter 

 as above under N. 



[EE.] From isobuti/ric acid [Vol. II] 

 and acetic aldehyde [92] through tri- 

 methylethylene-lactic acid (see under 

 acetone [106 ; K]), and then through 

 tertiary amyl alcohol, &c., as above. 



[PP.] Pentane gives formic aldehyde 

 (0-88 per cent.) among the products of 



