1,3-Dipolar cycloaddition reactions of 1-(4-phenylphenacyl)-1,10-phenanthrolinium N-ylide with activated alkynes and
F Dumitrascu1, M R Caira, C Draghici
1Centre of Organic Chemistry C. D. Nenitzescu, Romanian Academy, Spl. Independentei 202B, Bucharest 060023, Romania. fdumitra@cco.ro
Abstract:
The 3+2 cycloaddition reaction of 1-(4-phenylphenacyl)-1,10-phenanthrolinium ylide 4 with activated alkynes gave pyrrolo[1,2- 4a][1,10]phenanthrolines 6a-d. The "one pot" synthesis of 6a,b,d from 4, activated alkenes, Et(3)N and tetrakis-pyridine cobalt (II) dichromate (TPCD) is described. The helical chirality of pyrrolophenanthrolines 6b-d was put in evidence by NMR spectroscopy.
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