Transition metal diene complexes in organic synthesis. 3. Iron mediated spiroannulation to spiro[1,2,3,4-tetrahydroquinoline-4,1'-cyclohexane] system and rearrangement to a dihydroindole derivative.
In: Angewandte Chemie, Jg. 101 (1989) ; Nr. 12, S. 1745-1747
Zeitschriftenaufsatz / Fach: Chemie
The cyclohexadiene complex I underwent spirocyclization with 3,4-R2R3C6H3NHR1 (R1 = H, R2 = H, Me, R3 = H, MeO, Me; R = Me, R2 = R3 = H) followed by demetalation to give the spiroquinolinecyclohexane derivs. II. II (R1 = Me; R2 = R3 = H) rearranged on SiO2 to give the indole III. I was prepd. by acylation of the cyclohexadiene complex IV followed by hydride abstraction. The structure of I (R1 = R2 = H, R3 = MeO).Fe(CO)3 was detd. by x-ray crystallog.