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2868 cyclopentyl-2-d ethyl ether (4), trans-cyclopentyl-2-d ethyl ether (5), firebrick 60-80 column at 150OC. The samples collected in this way and cyclopentyl-l-d ethyl ether (6)were prepared by the Williamson were purified again by G C at 90 OC for cyclopentyl-2-d ethyl ether synthesis from 1,2, and 3, respectively. In a typical preparation, 1.55 and at 150O C for cyclopentanol-2-d. Only small samples amounting g of sodium was dispersed by stirring in refluxing xylene under a to 200-300 mg of better than 99% pure products were isolated. blanket of nitrogen. The xylene was replaced with 40 ml of ether, and The *HNMR spectra for cyclopentanols, cyclopentyl ethyl ethers a solution of 5.7 g of 3 in 20 ml of ether was added dropwise in 2 h with and trifluoroethyl ethers were taken in CHC13, CC14, and benzene, vigorous stirring. The reaction mixture was allowed to stand overnight, respectively. GC retention times of the products isolated in solvolysis and 10.3g of freshly distilled ethyl iodide was added dropwise into the were identical with those of the compounds prepared independently resulting sodium alkoxide solution while a slight reflux of ether was as described above; H NMR spectra were consistent in all cases with maintained. After standing overnight, 5 g of crude product 6 was the assigned structures. collected from the reaction mixture by distillation through a short Acknowledgment. W e are grateful to the Research Council Vigreux column at 120- 130O C . A small quantity was purified by G C of Croatia, the National Institutes of Health, Bethesda, Md., on an 8 ft X 1/4 in. column containing 20% Carbowax 20M on firebrick 60-80. 2H NMR spectrum of 6 ( 1