Fischer indole synthesis Grignard

Fischer indole synthesis Friedel-Crafts Grignard reaction... 

The Fischer indole synthesis has also been employed. The nitrile (XXXVIII) reacts with the Grignard reagent prepared from y-ethoxy-propyl bromide to give an intermediate (XXXIX) which in the presence of acid generates the cyclic ketone XL. The phenylhydrazone of the last can be cyclized to sempervirine (XXXV) (24). 

The Bartoli-indole synthesis utilizes the [3,3]-rearrangement of an 0-vinyl-iV-arylhydroxylamine intermediate to form indoles through a similar rearrangement and condensation process as the Fischer-indole synthesis f Scheme 14.7a). The rearrangement precursor 59 is generated from the addition of a vinyl Grignard reagent to a nitroarene. The... 

The pyridine-N-oxide 245 was converted into the cyanopyridine 246 and its isomer (Scheme 80). Grignard reaction, Fischer s indole synthesis, and N-protection gave a pyridinyl indole 247. Selenium dioxide selectively oxidized the methyl group to give the isonicotinic acid. The synthesis of Flavocarpine (244) was finally accomplished by a set of standard reactions as outlined in Scheme 80 (87TL5259). 

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