2193
z),
produced cis-2-methylthiocyclopentanol (9.8 g, 74 bp 52-54’ (0.3 mm); nmr 6 4.05 (m, 1 CHOH), 3.03 (d, 1, J = 2.5 Hz, OH), 2.95 (m, 1, CHSCH,), 2.08 (s, 3, SCH,), and 1.74 (m, 6, (CHr),). 2-Methoxy-1-propanol and 1-methoxy-2-propanol were prepared by the acid-catalyzed ring opening of propylene oxide in methanol according to a known procedure,26 and the isomers were separated by preparative glpc. 1-Methylthio-2-propanol was prepared by the procedure of Bordwell and A n d e r ~ e n : ~bp ? 67-69’ (20 mm) [liL27 bp 55-58” (10
mm)l.
2-Methylthio-1-propanol was prepared as follows : a mixture of 1-propenyl acetate (10 g, 0.1 mol), methanethiol (60g), and benzoyl (26) S. Winstein and L. L. Ingraham, J . Amer. Chem. Soc., 74, 1160 (1952). (27) F. G. Bordwell and H. M. Andersen, ibid., 7 5 , 4959 (1953).
Anodic Oxidations. 2-Methoxyethanol
peroxide (0.5 g) was illuminated with a uv lamp as described earlier for cis-2-methylthiocyclopentanol. The 2methylthiopropyl acetate obtained (4.8 g, 34z,bp 128”)was hydrolyzed with 10% KOH solution (60 ml) at room temperature. The mixture was extracted with ether several times, and the combined extracts were washed with water saturated with sodium chloride, dried (MgS04),and concentrated. The product was separated and purified by preparative glpc; overall yield 18%; bp 65-71” (12 mm); nmr (CDCl,) 6 3.55 (d, 2, J = 6.0 Hz, CH*OH),2.85 ( s , 1, OH), 2.79 (m, 1, CHSCH3, 2.05 (s, 3, SCH,), and 1.27 (d, 3, J = 6.0 Hz, CHCH,).
Acknowledgment. We are indebted to Dr. Wesley Huntress of the Jet Propulsion Laboratories, Pasadena, for his help with regard to both the instrumental and conceptual aspects of this work.
IX.
Anodic Oxidation of
Sidney D. ROSS,*John E. Barry, Manuel Finkelstein, and Eric J. Rudd Contribution front the Sprague Research and Development Center, Sprapue Electric Company, North Adams, Massachusetts 01247. Received August 25, 1972 Abstract: The anodic oxidation of 2-methoxyethanol in the presence of tetraethylammonium fluoroborate as supporting electrolyte results in the formation of formaldehyde, bis(2-methoxyethy1)formal (I), 2-hydroxyethyl-2’methoxyethylformal(IT), and 2,4,6,9-tetraoxadecane(111), with the major oxidation products resulting from attack
on the ether rather than the alcohol function of 2-methoxyethanol. With tetraethylammonium nitrate as supporting electrolyte, an additional product, 3-hydroxymethyl-2,4,7-trioxaoctane (IV), is obtained. The mechanisms of these oxidations have been discussed.
T
he saturated aliphatic alcohols and ethers have ionization potentials exceeding 9 eV. Since there is a parallelism between anodic oxidation potentials and gas-phase ionization potential^,^ it is not surprising that the anodic oxidation of aliphatic alcohols and ethers requires extreme positive potentials. By using fluoroborates as the supporting electrolyte, it is possible t o extend the potential range to beyond 3.0 V us. Ag/Ag+ M),5and to determine the half-wave potentials for oxidation of aliphatic alcohols by cyclic voltammetry. fi Sundholm’ has shown that methanol and ethanol can be electrooxidized to give, in good yield, aldehydes with sodium alkoxides as the supporting electrolytes and acetals with perchlorates or fluoroborates as the supporting electrolytes. The proposed mechanism involves reaction I as the primary process, with subse-
REHOH + 2e + H+
RCH~OH+
quent chemical steps leading t o products.
(1)
Shono and
(1) A. Streitwieser, Jr., Progr. Phys. Org. Chem., 1, 1 (1963). (2) J. L. Franklin, J. G . Dillard, H. M. Rosenstock, J. T. Herron, I
