furfural-yielding
carbohydrates. They conclude that raw cotton contains no appreciable
quantity of pentosane.
FOOTNOTES:
[8] This paper appears during the printing of the author's original MS.
[9] This paper appears during the printing of the author's original MS.
SECTION VI. THE LIGNOCELLULOSES
(p. 131) ~Lignocellulose Esters.~--By a fuller study of the ester
reactions of the normal celluloses we have been able to throw some light
on the constitutional problems involved; and we have extended the
investigations to the jute fibre as a type of the lignocelluloses, from
the results of which we get a clearer idea of the relationships of the
constituent groups.
Taking the empirical expression for the complex, i.e. the entire
lignocellulose, the formula C_{12}H_{18}O_{9}, we shall be able to
compare the ester derivatives with those of the celluloses, which we
have also referred to a C_{12} unit. But we shall require also to deal
with the constituent groups of the complex, which for the purposes of
this discussion may be regarded as (a) a cellulose of normal
characteristics--cellulose alpha; (b) a cellulose yielding furfural on
boiling with condensing acids--cellulose beta; and (c) a much
condensed, and in part benzenoid, group which we may continue to term
the lig_none_ group.
The latter has been specially examined with regard to its proportion of
OH groups, as a necessary preliminary to the investigation of esters, in
producing which the entire complex is employed. It will be shown that
the ester groups can be actually localised in various ways, as in the
main entering the cellulose residues alpha and beta. But that the
lignone group takes little part in the reactions may be generally
concluded on the evidence of its non-reactivity as an isolated
derivative, (1) By chlorination, &c. it is isolated in the form of an
amorphous body, but of constant composition, represented by the formula
C_{19}H_{18}Cl_{4}O_{9}. This compound, soluble in acetic anhydride, was
boiled with it for six hours after adding fused sodium acetate, and the
product separated by pouring into water. The dilute acid filtered from
the product contained no hydrochloric acid nor by-products of action.
The product showed an increase of weight of 7.5 p.ct. For one acetyl per
1 mol. C_{19}H_{18}Cl_{4}O the calculated increase is 8.0 p.ct. It is
evident from the nature of the derivative that this result cannot be
further verified by the usu
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