Migration 4-quinolones

Apparently, the above results were quite contrary to those observed in the photocyclization of 7V-benzoylenamines described in Section Il,A,l,a. N-Acylanilides carrying an electron-withdrawing group in the ortho position underwent smooth photocyclization exclusively to the root of the substituent that was then migrated in a 1,5 manner suprafacially to afford the lactam (5), having the substituent in the 3 position of the quinolone structure. 

Spath (178) believed that the quinoline ring system was present in cytisine, although he observed that no migration of the V-methyl group took place when model compounds, l,8-dimethyl-2-quinolone and... 

Jenekhe and coworkers found that DDQ converts anthrazo-line 7 to heptacyclic bis(indolo[l,2-a]quinolone) 8 (equation 3) [19]. Youn and Jang used DDQ to convert Af-Ts-2-alkenylanilines into indoles via, it is proposed, a radical cation generated by SET (equation 4) [20]. In the case of p,p-disubstituted 2-alkenylanilines, the 2,3-disubstituted indole product is derived from a C-2 to C-3 aryl migration via a phenonium ion (equation 5). 

Quinolones by migration of carbon-carbon double bonds-quinolines s. lA, 749 -Pyrrolo[3,2,l-ij]-... 

Quinolones by migration of a carbon-carbon double bond 14, 749... 

Very recently, Namgoong and co-workers reported a homologatimi reactimi via further utilization of these zincated heterocyclic intermediates with trimethyl borate [71]. For example, treatment of isoquinoline with TMP-zincate LiZn(TMP) Bu2 followed by addition of B(OMe)3 triggered migration of both the Bu group and zinc moiety to produce a 1,2-bismetallic species 39, which could be further quenched to give a 3,4-dihydroisoquinoline product (Fig- 20). These reactions could also take place with quinolone, but with lower selectivity, as mentioned above. 

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