C NMR was extremely useful because of the characteristic chemical shifts of the interior carbons and the expected T, increases [191 of the quaternary carbons. All "cascade" compounds were purified by nonaqueous, reverse-phase flash column chromatography. Correct elemental analyses were obtained for all new compounds. I3C NMR assignments are based on calculated values, signal intensities, and DEPT NMR experiments; consecutive numbering beginning at the central quaternary carbon simplifies description due to symmetry. Selected physical data for 9-13: 9: 'H NMR (360MHz. CDCI,): 6 = 1.10-1.65 (m. SOH). 2.00-2.21 (m, 16H), 3.35 (br t. 24H). 4.45 (s, 24H), 7.28 (s, 60H); 13C NMR (360 MHz,
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