S56 



SULPHUR COMPOUNDS 



[165 N-167 A. 



From mannitol [5l] through 

 hexane (see under n-hexyl alcohol [23 ; 

 B]) and carbon disulphide } and then as 

 above. 



NOTE : All generators of n-hexane referred 

 to under n-hexyl alcohol [23] thus become, 

 with carbon disulphide, generators of this mus- 

 tard oil. n-Hexyl alcohol itself is a generator 

 of hexane through n-hexyl iodide and reduction 

 of the latter. 



166. Allyl Isotliiocyanate or 

 Thiocarbimide ; Mustard Oil. 



CH 2 :CH.CH 2 .NCS 



NATURAL SOURCES. 



Occurs as glucoside, potassium myro- 

 nate or sinigrin, in black mustard from 

 the seeds of Sinapis nigra a,ndS.juncea. 

 (For references see Gildemeister and 

 Hoffmann's l Die aetherischen Oele/ 

 p. 533 ; Gadamer, Arch. Pharm. 235, 

 44 ; Ber. 30, 3323.) 



A glucoside (probably sinigrin) is 

 contained in horse-radish root, Cochlearia 

 armoracia (Hubatka, Ann. 47, 153; 

 Sani, Schimmel's Ber. April 1 894 ; 

 Gadamer, Arch. Pharm. 235, 577). 



The root of garlic-mustard (Sisym- 

 brium alliaria) gives an oil on distilla- 

 tion which apparently contains allyl 

 mustard oil (Wertheim, Ann. 52, 52 ; 

 Pless, Ann. 58, 38). 



The plant and seeds of penny-cress, 

 Thlaspi arvense, give an oil which, ac- 

 cording to Pless (loc. cit. 36), contains 

 allyl mustard oil. The recent work of 

 Semmler (Arch. Pharm. 230, 434) 

 throws doubt on the existence of allyl 

 mustard oil in these two last plants. 

 According to Ritthausen (Journ. pr. 

 Ch. [2] 24, 273) sinigrin (potassium 

 myronate) occurs in the seeds of turnip, 

 Brassica rapa. 



According to Bokorny (Ch. Zeit. 24, 

 771; 817; 832) Iberis amara, I. um- 

 bettata, and /. sempervirens, scurvy- 

 grass (Cocklearia officinalis), winter cab- 

 bage (Brassica oleracea\ and radish (Ra- 

 phanus sativus), contain some glucoside 

 which yields mustard oil (? allyl) under 

 the influence of myrosin. (For occur- 

 rence of mustard oil in seeds of Cruci- 



ferse see also Jorgensen, Ch. Centr. 

 1898, 2, 927; 1899, 2, 781). 



NOTE : Many mustard oils which were at 

 one time thought to contain allyl have by 

 later investigation been proved to be isothio- 

 cyanates of other radicles. 



SYNTHETICAL PROCESS. 



[A.] From glycerol [48] through 

 allyl iodide (see under iso butyl alcohol 

 [18 ; D]) and thiocyanic acid [174], by 

 the distillation of potassium or silver 

 thiocyanate with allyl iodide (Zinin, 

 Ann. 95, 128 ; Berthelot and De Luca, 

 Ann. Chim. [3] 44, 495 ; Comp. Rend. 

 41, 21). The normal ester produced 

 at first is transformed into the mustard 

 oil by the action of the heat (Oeser, 

 Ann. 134, 7; Billeter, Ber. 8, 464; 

 Gerlich, Ann. 178, 89). 



NOTE : Sinigrin when hydrolysed at o by 

 myrosin (the mustard seed enzyme) gives, with 

 allyl mustard oil, a trace of allyl thiocyanate 

 (E. Schmidt, Ber. 10, 187). The latter can be 

 synthesised from ammonium thiocyanate and 

 allyl bromide in alcoholic solution at o (Ger- 

 lich, loc. cit. 85), or from allyl iodide and potas- 

 sium hydrosulphide through allyl mercaptan, 

 the lead compound of the latter giving allyl 

 thiocyanate on treatment with cyanogen chlor- 

 ide in ethereal solution (Billeter, loc. cit.). 



167. Crotonyl Isotliiocyanate 



or Thiocarbimide; 

 Crotouyl Mustard Oil. 



C 4 H 7 . NCS = 

 CH 2 : CH . CH 2 . CH 2 . N : C : S (?) 



NATURAL SOURCES. 



This mustard oil is apparently con- 

 tained in the oil-cake from rape seed 

 (Jorgensen, Ch. Centr. 1899, 2, 781; 

 Landw. Versuchs-Sta. 52, 269, &c.); 

 also in the seeds of Brassica glauca, B. 

 dichotoma, &c. (Ibid. Ch. Centr. 1898, 2, 

 928), and B. napus (Sjollema, Rec. Tr. 

 Ch. 20, 237). 



SYNTHETICAL PROCESSES. 



[A.] From uobutyl alcohol [18] 

 through isobutylene bromide (see under 

 isobutyl alcohol [18; A] and tertiary 

 butyl alcohol [19; B]), and carbon 



