Reaction Steps
To a stirred solution of t-butyl nitrite (271 mg, 0.312 ml, 2.63 mmol) in DMF (15 ml) at 60-65° C. was added 7-allyloxy-3-amino-1,2,4-benzotriazine-1,4-dioxide 23 (205 mg, 0.875 mmol) in small portions over 5 min. After 30 min additional t-butyl nitrite (271 mg, 0.312 ml, 2.63 mmol) was added, and shortly thereafter the deep red solution effervesced and lightened appreciably in color over a period of a few minutes. After an additional 30 min the resultant orange solution was reduced under vacuum to a brown solid which was sequentially flash chromatographed (10% EtOAc/CH2Cl2) and crystallized (CH2Cl2/petroleum ether) to give 72 mg (38% yield) of the product 24 as light orange crystals, mp 147-148° C. NMR: δ (400 MHz, d6-acetone) 4.89 (2H, ddd, H-1′, J1′,2′=5.5, J1′,3′cis=J1′,3′trans=1.5 Hz), 5.36 (1H, ddd, H-3′, J3′,2′cis=10.5, J3′,3′=3 J3′,1′=1.5 Hz), 5.52 (1H, ddd, H-3′, J3′,2′trans=17.5, J3′,3′=3, J3′1′=1.5 Hz), 6.14 (1H, ddt, H-2′, J2′,3′cis=10.5, J2′,1′=5.5 Hz), 7.70 (1H, d, H-8, J8,6=2.5 Hz), 7.74 (1H, dd, H-6, J6,5=9.5, J6,8=2.5 Hz), 8.33 (1H, d, H-5, J5,6=9.5 Hz), 8.93 (1H, s, H-3). UV: λ 425, 410, 365, 355, 320, 245, 200. MS m/z/(relative intensity) 220(4), 219(34, M+), 103(4), 77(4), 75(4), 63(13), 62(4), 42(3), 41(100), 39(16). Anal. Calc'd. for C10H9N3O3: C, 54.79; H, 4.14; N, 19.17. Found: C, 54.73; H, 4.16; N, 19.15.
