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We report on a 2H NMR study of several selectively deuterated stearic acids and a-deuterated n-bromooctane-d, acting as guests in urea adducts. The stearic acid chain assumes an extended all-trans configuration along the channel axis at all temperatures; it is, except for the somewhat flexible end segment, immobile up to 140 K, when onset of discrete jumps of threefold symmetry about the channel axis was detected. The end-methyl dynamics is more complex, with rapid local fluctuations superimposed on the molecular jumps. We found this combined mode to be predominantly diffusive. Bromooctane-d2 labeled at the a position was found to diffuse continuously about an axis perpendicular to the C-D bond, in accord with an extended all-trans chain conformation. With the shorter chain, onset of mobility is shifted to lower temperatures.

indole-1-acetate was hydrogenated at an initial pressure of 50 96-98'; v~~c l ' 1736 ( C 4 ester) and 1682 om-' (CZO amide); psi in 200 ml of ethanol in the presence of 1 g of platinum oxide.XZt' " sh 281 mp ( E SOOO), sh 289 (9700), and 314 (15,500).After 4 hr the catalyst was filtered, the filtrate wm concentrated, Anal. Calcd for C~HuNt07: C, 59.40; H, 5.98; N, 0.93. and the residual oil was chromatographed on neutral alumina.Found: C, 59.51; HI 5.98; N, 6.84.Fractions eluted with ether were wmbined and concentrated, and the residual solid wm recrystallized from ethyl acetatehexane to give 3.0 K (30%) of ethyl 3-carbethoxy-1,2,3,4-tetraAcknowledgment*-we thank Dr* R* *Imond and k h . M. c. Christie for many of the analytical and hydro-7,8-dimethox~-2-oxopyrimido [ 1,2-a] indole-1-acetate: mp spectral resdts. 5-Trimethylsilylindole has been synthesized starting from indole which waa N-benzylated and brominated in the 5 position, metalated to 5-lithio-N-benzylindolineJ and treated with trimethylchlorosilane to yield 5-trimethylsilyl-N-benzylindoline. Catalytic hydrogenolysis in the presence of acetic anhydride gave 5-trimethylsilyl-N-acetylindoline, which was hydrolyzed by KOH in diethylene glycol to btrimethylsilylindoline, which in turn was converted into 5-trimethylsilylindole by catalytic dehydrogenation in boiling xylene in the presence of palladium-charcoal. 5-Trimethylsilylgramines were synthesized. 5-Trimethylsilylgramine methiodide was converted into the nitrile by reaction with sodium cyanide and the latter waa hydrolyzed to btrimethylsilylindole-3-acetic acid, or reduced to 5-trimethylsilyltryptamine.

Michael addition reactions can be efficiently catalysed, giving high yields, by K F in aprotic solvents containing 1,4,7,10,13,16-hexaoxacyclo-octadecane (1 8crown-6).THE ability of solubilized 'naked' fluoride ion to behave, in aprotic solvents, as a strong base and nucleophile was recently described.l There have been some reports regarding the ability of alkali metal fluorides to catalyse Michael 0.03-0.05 equiv. of 18-crown-6, and ca. 0.2 equiv. of K F (Table ).A typical procedure is exemplified by the addition of nitromethane to chalcone. To a solution of 18-crown-6 (0.03 mmol) in dry MeCN (65 ml), dry K F (ca. 1 mmol) was added followed by MeNO, (0.1 mol) and chalcone (5 mmol). The mixture was stirred a t 81 "C for 1.5 h. MeCN was removed in vacuo, CH,CI, was added, and the organic layer was washed with 2~ HC1. Removal of CH,Cl, left a solid

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