An MC-SCF Study of the Mechanisms for 1,3-Dipolar Cycloadditions
4642 J. Am. Chem. SOC.1987, 109, 4642-4648 with a = 14.305 A, b = 12.995 A, c = 14.595 A, fi = 93.16O, V = 2709 Forschungsgemeinschaft, the Fonds der Chemischen Industrie, A’, and Z = 8. and the BASF AG as well as the large-scale preparation of in- A total of 4165 reflections were recorded on a Philips PW 1100 dif- termediate 18 by the Ciba-Geigy AG are gratefully acknowledged. fractometer in the 8-28 scan mode with 28 = 6-46’ using Ka Mo We express our appreciation to Dr. H. Fritz and Dr. D. Hunkler monochromatized radiation (A = 0.709 26 A). The unique reflections were used to solve the structure with MULTAN for NMR and to Dr. J. Worth for MS measurements. 78 programs. The 40 non-hydrogen atoms were anisotropically refined with block diagonal least squares (R = 0.1 10). All 36 hydrogen atoms Registry No. 1, 89683-62-5; 3, 465-73-6; 4,4723-74-4; 5, 72448-17-0; were localized on a F map. The conventional R factor for the 3401 6, 4309-87-9; 9, 108590-43-8; 10, 3647-99-2; 11, 108510-50-5; 12, reflections considered observed with I > 244was 0.052. 65879-03-0; 13, 108510-51-6; 14, 65879-05-2; 15, 65879-04-1; 17, X-ray Crystallographic Analysis for 55. The dimethyl ester crystal- 108510-52-7; 17 (C,-symmetrical isomer), 108510-54-9; 18, 65879-09-6; lized in a monoclinic system, space group P2,/n (No. 14, centrosym- 19, 108510-53-8; 21, 65879-06-3; 26, 108533-20-6; 27, 1076-13-7; 30, metric, racemate), with a = 17.251 A, b = 6.073 A, c = 16.512 A, fi = 108510-55-0; 31, 3648-03-1; 32, 3648-04-2; 40, 65879-07-4; 42, 65879- 92.24’, V = 1729 A3and Z = 4.
[Show full text]