Never a dull moment with praseodymium metal

Unexpectedly, a mixture of bismuth N , N ′-bis(2,6-diisopropylphenyl)formamidinates in three different oxidation states namely, [Bi I 2 (DippForm) 2 ] ( 1 ), [Bi II 2 (DippForm) 2 (C 6 F 5 ) 2 ] ( 2 ) and [Bi III (DippForm) 2 (C 6 F 5 )] ( 3 ), together with [Pr(DippForm) 2 F(thf)]·PhMe ( 4 ), [ p -HC 6 F 4 DippForm]·0.5thf ( 5 ), and a ring-opened tetrahydrofuran [ o -HC 6 F 4 O(CH 2 ) 4 DippForm] ( 6 ) was obtained by the reaction of an excess of praseodymium metal with tris(pentafluorophenyl)bismuth, [Bi(C 6 F 5 ) 3 ]·0.5dioxane, and bulky N , N ′-bis(2,6-diisopropylphenyl)formamidine (DippFormH) in tetrahydrofuran. Similar reactions between praseodymium metal, [Bi(C 6 F 5 ) 3 ]·0.5dioxane and 3,5-diphenylpyrazole (Ph 2 pzH), or 3,5-di- tert -butylpyrazole ( t Bu 2 pzH), yielded the paddlewheel dibismuthanes [Bi II 2 (Ph 2 pz) 4 ]·dioxane ( 7 ) and [Bi II 2 ( t Bu 2 pz) 4 ] ( 8 ) respectively. [Bi I 2 (DippForm) 2 ], [Bi II 2 (DippForm) 2 (C 6 F 5 ) 2 ] [Bi III (DippForm) 2 (C 6 F 5 )], [Pr(DippForm) 2 F(thf)]·PhMe, [ p -HC 6 F 4 DippForm]·0.5thf, and a ring-opened thf [ o -HC 6 F 4 O(CH 2 ) 4 DippForm] were obtained by the reaction of Pr metal with [Bi(C 6 F 5 ) 3 ]·0.5dioxane, DippFormH in thf.