Abstract
Convenient methods for the regioselective formylation of tetrahydro[1,4]oxazino[2,3-f] and [3,2-g]indole derivatives 3 and 4 are described.
The obtained formyl derivatives 6 and 8 were further transformed in four steps
into the unknown hexahydro[1,4]oxazino[2,3-h] 1 and [3,2-j]β-carbolines 2.
Key words
oxazinoindoles - regioselective formylation - Vilsmeier-Haack
reaction - Rieche reaction
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