Neue methode zur regiospezifischen substitution einiger reaktionsträcer N-heteroaromatischer ringsysteme

N-Trifluoromethanesulfonyl-heteroarylium salts 1 react with phosphanes 2 to give the C4- or C2-substituted products 4 or 5. By means of a similar procedure, bisphosphonium salts 6 and 7 are formed. The reaction of sodium azide (8), and 6 yields the iminophosphorane 10 via the intermediate 9.