OXYCELLULOSES AND THE MOLECULAR WEIGHT OF CELLULOSE.

H. Nastukoff (Berl. Ber. 33 [13] 2237).

(p. 61) The author continues his investigations of the oxidation of cellulose. [Compare Bull. Mulhouse, 1892.] The products described were obtained by the action of hypochlorites and permanganates upon Swedish filter paper (Schleicher and Schüll).

4. Oxidation by hypochlorites.—(1) The cellulose was digested 24 hrs. with 35 times its weight of a filtered solution of bleaching power of 4°B.; afterwards drained and exposed for 24 hrs. to the atmosphere. These treatments were then repeated. After washing, treatment with dilute acetic acid and again washing, the product was treated with a 10 p.ct. NaOH solution. The oxycellulose was precipitated from the filtered solution: yield 45 p.ct. The residue when purified amounted to 30 p.ct. of the original cellulose, with which it was identical in all essential properties.

The oxycellulose, after purification, dried at 110°, gave the following analytical numbers:

	C	43.64	43.78	43.32	43.13
	H	6.17	6.21	5.98	6.08

Its compound with phenylhydrazine (loc. cit.) gave the following analytical numbers:

0.78

0.96

0.84

(2) The reagents were as in (1), but the conditions varied by passing a stream of carbonic acid gas through the solution contained in a flask, until Cl compounds ceased to be given off. The analysis of the purified oxycellulose gave C 43.53, H 6.13.

(3) The conditions were as in (2), but a much stronger hypochlorite solution—viz. 12°B.—was employed. The yield of oxycellulose precipitated from solution in soda lye (10 p.ct. NaOH) was 45 p.ct. There was only a slight residue of unattacked cellulose. The analytical numbers obtained were:

Oxycellulose	C	43.31	43.74	43.69
"	H	6.47	6.42	6.51
	________________________
Phenylhydrazine compound	N		0.62	0.81

B. Oxidation by permanganate (KMnO₄). (1) The cellulose 16 grms. was treated with 1100 c.c. of a 1 p.ct. solution of KMnO₄ in successive portions. The MnO₂ was removed from time to time by digesting the product with a dilute sulphuric acid (10 p.ct. H₂SO₄). The oxycellulose was purified as before, yield 40 p.ct. Analytical numbers:

Oxycellulose	C		42.12	42.9
"	H		6.20	6.11
	________________________
Phenylhydrazine compound	N	1.35	1.08	1.21

(2) The cellulose (16 grms.) was digested 14 days with 2500 c.c. of 1 p.ct. KMnO₄ solution. The purified oxycellulose was identical in all respects with the above: yield 40 p.ct. C 42.66, H 6.19.

(3) The cellulose (16 grms.) was heated in the water-bath with 1600 c.c. of 15 p.ct. H₂SO₄ to which were added 18 grms. KMnO₄. The yield and composition of the oxycellulose was identical with the above. It appears from these results that the oxidation with hypochlorites acids 1 atom of O to 4-6 of the unit groups C₆H₁₀O₅; and the oxidation with permanganate 2 atoms O per 4-6 units of C₆H₁₀O₅. The molecular proportion of N in the phenylhydrazine residue combining is fractional, representing 1 atom O, i.e. 1 CO group reacting per 4 C₃₆H₆₀O₃₁ and 6 C₂₄H₄₉O₂₁ respectively, assuming the reaction to be a hydrazone reaction.

Further investigations of the oxycelluloses by treatment with (a) sodium amalgam, (b) bromine (water), and (c) dilute nitric acid at 110°, led to no positive results.

By treatment with alcoholic soda (NaOH) the products were resolved into a soluble and insoluble portion, the properties of the latter being those of a cellulose (hydrate).

Molecular weight of cellulose and oxycellulose.—The author endeavours to arrive at numbers expressing these relations by converting the substances into acetates by Schutzenberger's method, and observing the boiling-points of their solution in nitrobenzene.