A general method for the preparation of cis-annelated rings

Amino-Claisen rearrangements of N-vinylisoquinuclidines in novel approaches to the synthesis of hydroisoquinolines and hydrophenanthridines

“…A,4a'1obA8-8-(l,l-Ethylenedi0xyeth-l-yl)-l-0x0deCahydr0phenanthridine (21). A solution of 412 mg (1.43 mmol) of 2-(cyclohex-2-en-l-on-3-yl)-endo-arid -exo-7-(l,l-ethylenedioxyeth-l-yl)-2azabicyclo[2.2.2]oct-5-ene (20) in 50 mL of benzene was saturated with anhydrous (passed first through concentrated H2SO4) HC1 and refluxed for 3.5 days.…”

“…This gave a brown oil which was purified by preparative TLC on silica gel (1:1 ether-hexane), yielding a clear oil (0.93 g, 91%) characterized as the evelohexadiene derivative 30: IR (CC14) 3440, 3025, 2970, 2945, 1730,1665,1510,1250 cm-1; UV (CH3CN) max 299 nm U 9465); NMR (DCC13) 1.22 (t, 3 H, J = 7 Hz, -OCH2CH3), 2.32 (s, 3 H, COCH3), 2.06-2.80 (m, 3 H, H-l and -2), 3.06 (dd, 1 H, J = 13.5 and 6 Hz, -NCH-H), 3.31 (dd, 1 H, J = 13.5 and 6 Hz, -NCH-H), 4.12 (q, 2 H. J = 7 Hz, -OCH,CH3), 5.31 (m. 1 , -NH-). 6.16 (m, 2 , H-5 and -6), 6.89 (m, 1 H, H-4); l:iC NMR (DCC13) 14.6 (q, -OCH2CH3), 23.4 (t, C-2), 25.1 (q, COCH3), 34.5 (d, C-l), 43.6 (t, -NCH2->, 60.7 (t, -OCHoCHs), 124.7 (d, C-5), 133.4 (d, C-6), 135.3 (s, C-l), 136.4 (d, C-41, 156.9 (s, -NHCO-), 198.3 (s,-COCH3) ppm; mass spectrum, m/e (relative intensity) 223 (P, 9), 178 (10), 134 (21), 122 (100); high-resolution mass spectrum, m/e 223.12114 (Ci2Hi7N03 requires 223.12084). 0-(2,2,2-Trichloroethyl) JV-(3-Acetyl-1,2-dihydrobenzyl)carbamate (31).…”