. Su These diicd: Reeds are the tonka beans of commerce as they are sold to the 
os merchants and exporters in Ciudad Bolivar. By the end of May or the ceeining of 
I June the crop is completed. 
Before the bearts are exported they go dareaeh a process of crystallizing by being 
. steeped in strong rum or alcohol. Casks open at one end are filled with the beans 
_ to within about a foot from the top. The rum is then poured in until the cask is full — 
__ when it is covered by layers of gunny bags. After 24 hours the rum not absorbed is 
_ fun off and the beans are spread out to dry in a current of air. When first taken 
_ out the beans are of dark brown colour and are swollen with the absorbed fluid. On 
drying they shrink and become covered with coumarin crystals. Ae 
 : The price of the beans varies greatly. In 1912, the crop being small, the value 
rose to § 4.87 per pound. The next year it fell-to less than f 1.— per pound. During 
= the fiscal year ending on the 30th. of June, 1913, the United States imported 783888 eee oe 
of tonka ere valued at § 1140 409.—. 
= “On the Geet of coumarin with alkaline: bisulphites nothing was known so far, Sie 
__ with one exception, Rochleder having, many years ago, described a compound derived — 
— from zesculetin (a dihydroxycoumarin) a derivative which he considered an addition 
_ product of sodium bisulphite to asculetin, but which at a later date was recognized 
by Liebermann as a sulphonic derivative of hydro - esculetin'). Now F. D. Dodge?) anos 
has observed that coumarin and limettin (= citroptene, a dimethoxy-coumarin) readily __ 
yields well defined sulphonic derivatives. If coumarin is warmed on the water bath, | ey 
__ with six parts of a 20 per cent. sodium bisulphite solution, with frequent shaking, a 
solution results which, on cooling, solidifies to a mass of crystals, readily soluble in a 
_ water, C,;H;O2-NaHSO ;-H:0, the sodium hydrocoumarinsulphonate. The salt may be a. 
_ titrated with accuracy, giving results which indicate the absorption of one molecule — ee 
of alkaline hydroxide. When a concentrated solution of the compound is treated ae 
_ with caustic soda solution coumarin is precipitated which redissolves: on continued =< 
agitation, but on further ad- . oe : | : 
dition of alkali it is again — ! so 
_ separated. Finally coumarin aoe 4 os "ee erie 
_. ceases to separate and the — Sy DAHON re | % ee Na = 
liquid becomes permanently \/ oe, gee | NUL ae “8 
neutral. The explanation for 3 ey eeiege ee CH, sa 
=a phenomenon ae fol- ; es . 5 ene Ae ae Wy 
- lows: The crystalline sulphonate is a derivative ee | ae 
of hydrocoumarin, containing the lactone ring ve oe eae 
intact. Alkali splits off the sulpho group, | 4 aon Z 
liberating coumarin which recombines with the \ ees CH: SO,Na 
neutral sulphite, forming the open-chain hydro- - - CH, a 
coumaric. acid deri- — oe - Sodium hydrocoumarinic sulphonate. a 
 vative about after the : 
’ ; : OH 
3 pees. manner: — ee 
— | | : ; 4b Na8Oe a H20 Gy | | ; ae 
1) See also Berl. Berichte 35 aS a aon ; WS \ ce cH ee = 
(1902), 2919. —2) Journ. Americ. . \CO.Na aoe 
ce Chem. Soc. 88 (1916), 446. ne Sodium hydrocoumaric sulphonate. 
