C1(P(N=[N+]=[N-])(C2C=CC=CC=2)=[O:8])C=CC=CC=1.[CH2:18]([C:20]1[CH:21]=[CH:22][C:23](C(O)=O)=[N:24][CH:25]=1)[CH3:19].C([N:31]([CH2:34]C)CC)C.[CH2:36]([OH:43])[C:37]1[CH:42]=[CH:41][CH:40]=[CH:39][CH:38]=1>O1CCOCC1>[CH2:18]([C:20]1[CH:21]=[CH:22][C:23]([NH:31][C:34](=[O:8])[O:43][CH2:36][C:37]2[CH:42]=[CH:41][CH:40]=[CH:39][CH:38]=2)=[N:24][CH:25]=1)[CH3:19]Diphenylphosphoryl azide (4.04 g., 14.7 mmoles) was added to a solution of 5-ethylpyridine-2-carboxylic acid (2.22 g., 14.7 mmoles), triethylamine (1.485 g., 14.7 mmoles), and benzyl alcohol (1.75 g., 16.17 mmoles) in 1,4-dioxane (23.5 ml.), and the mixture heated under reflux for one hour. The 1,4-dioxane was removed under reduced pressure. A solution of the residue in toluene was washed successively with water, aqueous sodium bicarbonate, and brine, and was then dried over sodium sulfate. The toluene was removed and the residue recrystallized from 2-propanol to give benzyl (5-ethyl-2-pyridyl)carbamate (1.9 g., 50.5%), m.p. 125°-127°. An analytical sample had m.p. 127°-130°.
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