III. 0.1357 gram gave 0.0807 gram BaSO₄.

C[NH.C₆H₅]₂

/ \

/ O

/ /

Cal. for C₆H₃——SO₂

\

NO₂

Found.

I. II. III.

N = 10.58 10.85 —— ——

S = 8.06 —— 8.00 8.16

By this series of transformations it is possible to pass from one

anilid to the other, the steps being:

CO.NH.C₆H₅ C=N.C₆H₅ C[NH.C₆H₅]₂

/ / \ / \

/ / N.C₆H₅ / O

/ / / / /

C₆H₃——SO₂NH.C₆H₅ ➡ C₆H₃——SO₂ ➡ C₆H₃——SO₂

\ \ \

NO₂ NO₂ NO₂

This is of special interest as affording a means of passing from a

derivative of one of the chlorides, to a substance derived from the

other, by steps that can be clearly followed.

Conclusions.

In the course of this investigation several facts have been established.

1. By the methods described, the symmetrical chloride of

paranitroorthosulphobenzoic acid can be obtained in fine crystalline

form, perfectly free from its isomer, with an average yield of forty

percent.

2. By treatment of the chloride with benzene and aluminium chloride,

only one chlorine atom can be replaced by a phenyl group.

3. The barium salt of paranitroorthobenzoyl benzenesulphonic acid, when

perfectly pure, crystallizes constantly with seven molecules of water

of crystallization.

4. With alcohols, the symmetrical chloride yields directly the acid

etherial salt of paranitroorthosulphobenzoic acid, no evidence

having been obtained of an intermediate chloro-etherial salt. The

unsymmetrical chloride on the other hand yields the intermediate

product.

A Further Investigation of the Symmetrical Chloride of Paranitroorthosulphobenzoic Acid · 第 27 / 29 题