122.8, 125.5, 127.8, 130.3, 131.2, 135.6, 137.0, 176.4. Anal. Calcd for C14H12N20: C,

74.98; H, 5.39; N, 12.49. Found: C, 74.72; H, 5.54; N, 12.20.

 (1-Methyl-1H-pyrrol-2-yl)(1H-pyrrol-2-yl)methanone (6.5g): reddish prisms

(from chloroform/ hexanes); mp 131-132 C; yield, 75%; 1H NMR 6 3.97 (s, 3H), 6.18

(dd, J= 4.0, 2.4 Hz, 1H), 6.31 (dd, J= 6.1, 2.6 Hz, 1H), 6.87 (br s, 1H), 6.97 (br s, 1H),

7.05-7.07 (m, 2H), 9.90 (br s, 1H); 13C NMR 6 36.8, 108.1, 110.4, 116.8, 119.4, 123.8,

130.2, 130.3, 131.9, 174.8. Anal. Calcd for C1oHioN20: C, 68.95; H, 5.79; N, 16.08.

Found: C, 69.17; H, 5.79; N, 16.16.

 (4-Methylphenyl)[l-(triisopropylsilyl)-1H-pyrrol-3-yl]methanone (6.7a): white

prisms (from hexanes); mp 82-83 C; yield, 92%; 1H NMR 6 1.16 (d, J= 7.4 Hz, 18H),

1.47-1.55 (m, 3H), 2.48 (s, 3H), 6.84-6.85 (m, 2H), 7.31 (d, J= 7.8 Hz, 2H), 7.38 (s,

1H), 7.82 (d, J= 7.8 Hz, 2H); 13C NMR 6 11.5, 17.6, 21.5, 112.4, 125.3, 126.9, 128.8,

129.2, 131.6, 137.5, 141.7, 190.7. Anal. Calcd for C21H31NOSi: C, 73.84; H, 9.15; N,

4.10. Found: C, 73.97; H, 5.79; N, 16.16.

 (4-Nitrophenyl)[l-(triisopropylsilyl)-1H-pyrrol-3-yl]methanone (6.7b): yellow

prisms (from hexanes); mp 131-132 C; yield, 72%; 1H NMR 6 1.12 (d, J= 7.4 Hz,

18H), 1.43-1.51 (m, 3H), 6.76-6.77 (m, 1H), 6.81-6.83 (m, 1H), 7.33 (s, 1H), 7.96 (d, J

= 8.7 Hz, 2H), 8.32 (d,J= 8.7 Hz, 2H); 13C NMR 6 11.4, 17.6, 112.2, 123.4, 126.1,

126.2, 129.6, 132.3, 145.6, 149.3, 188.8. Anal. Calcd for C20H28N203Si: C, 64.48; H,

7.58; N, 7.52. Found: C, 64.84; H, 7.88; N, 7.46.

 [4-(Diethylamino)phenyl] [1-(triisopropylsilyl)-1H-pyrrol-3-yl]methanone

(6.7c): yellow prisms (from hexanes); mp 103-104 C; yield, 90%; 1H NMR 6 1.11 (d, J

= 7.4 Hz, 18H), 1.20 (t, J= 7.1 Hz, 6H), 1.42-1.50 (m, 3H), 3.42 (q, J= 7.1 Hz, 4H),