Bicyclic Ketones. II. The 2-Acetylbicyclo[2.2.1]hept-5-ene and 2-Acetylbicyclo[2.2.1]heptane Systems^1,2

Abstract

Dinwiddie and McManusVol. 30 temperature for 1 hr. and under reflux for 2 hr. with 1 g. of freshly prepared W-2 Raney nickel.27 The cooled mixture was filtered and the ethanol was removed affording 25 mg. (93.7%) of white solid with an infrared spectrum which was indistinguishable from that of racemic lactone 17. After two recrystallizations from hexane, 11 mg. of material with m.p. 119-121°wasobtained.

New Dienophiles: 1‐Acetylvinyl Arenecarboxylates. Reactivity toward cyclopentadiene and exocyclic dienes

“…In general, the stereoselectivity of these additions is not good ( Table 2). In most cases it tends to be the reverse of that of MVK+ cyclopentadiene (endolexo adduct ratio= 83 : 17 [20]). The structures of 5 and 6 were deduced from their 'H-NMR.…”

“…(A1203, F- 100, M + ) , 351 (8.2). 323 (23), 319 (9.6), 305 (26), 295 (15), 277 (20), 265 (13), 252 (20), 237 (23),221 (15), 165 (12) (12), 333 (11). 323 (21), 305 (18).…”

Reactions of .alpha.-alkoxy-.alpha.,.beta.-unsaturated carbonyl compounds

“…Acid catalysis (aluminum chloride or acetic acid) was likewise ineffective, The addition could be effected by heating the dienophile in a large excess of diene at 160-190 °C. Thus, 2 afforded a 54% yield of 17 and 3 afforded a 61% yield of 18 upon treatment with cyclopentadiene. Treatment of 2 and 3 with butadiene in a similar manner afforded cyclohexenes 19 (49% yield) and 20 (40% yield), respectively.…”

Les spectres de masse dans l' analyse 10e communication [1] les transferts d'hygrogène dans des cétones norbornyliques

“…De plus, il semble que le transfert C-5 B C-3 ne soit pas aussi favorable que l'6limination successive de cCtdne et de mCthyle, comme nous l'avons trouvC Cgalement pour l'endo-isocamphanone (10). [17]. I1 vaut presque toujours mieux sCparer les isomhres exo-et endo-immediatement aprZts la rCaction de DIELS et avant la r6duction catalytique, les propridtks chromatographiques des norbornanes isomkres &ant beaucoup plus semblables entre elles que celles des norbornhes (v. p. ex.…”

“…I1 vaut presque toujours mieux sCparer les isomhres exo-et endo-immediatement aprZts la rCaction de DIELS et avant la r6duction catalytique, les propridtks chromatographiques des norbornanes isomkres &ant beaucoup plus semblables entre elles que celles des norbornhes (v. p. ex. [18] et [17]). …”