| Abstract
| - The reaction of 2-ROC6H4I with [Pd2(dba)3]·dba (“Pd(dba)2”; dba = dibenzylideneacetone)in the presence of the appropriate ligand results in the formation of the arylpalladiumcomplexes trans-[Pd(C6H4OR-2)I(PPh3)2] (R = H (1a), C(O)Me (1b), C(O)CHCH2 (1c)) and[Pd(C6H4OR-2)I(bpy)] (bpy = 2,2‘-bipyridine; R = H (2a), C(O)Me (2b)). Complexes 1b and1c react with bpy in the presence of Tl(OTf) (OTf = OSO2CF3) to give the cationic species[Pd(C6H4OR-2)(bpy)(PPh3)]OTf (R = C(O)Me (3b), C(O)CHCH2 (3c)). Complex 1a reactswith carbon monoxide, yielding the insertion complex trans-[Pd{C(O)C6H4OH-2}I(PPh3)2](4a). Complexes 2a and 2b can also be carbonylated to give [Pd{C(O)C6H4OR-2}I(bpy)] (R= H (5a), C(O)Me (5b)). Complex 4a reacts with bpy and Tl(OTf), giving [Pd{C(O)C6H4OH-2}(bpy)(PPh3)]OTf (6a). The reaction of 2-ROC6H4I with Pd(dba)2 and isonitriles R‘NC givesrise to the complexes trans-[Pd{C(NR‘)C6H4OR-2}I(CNR‘)2] (R = H, R‘ = Xy = 2,6-dimethylphenyl) (7a), R‘ = tBu (7a*); R = C(O)Me, R‘ = Xy (7b), R‘ = tBu (7b*)). Complexes7a and 7b* can also be prepared by ligand displacement from 2a and 2b and XyNC andtBuNC, respectively. Complexes 2a and 2b react with R‘NC (1:1) to give [Pd{C(NR‘)C6H4OR-2}I(bpy)] (R = H, R‘ = Xy (8a), R‘ = tBu (8a*); R = C(O)Me, R‘ = Xy (8b)). Complex 7areacts with bpy in the presence of Tl(OTf), yielding [Pd{C(NR‘)C6H4OH-2}(CNR‘)(bpy)]OTf (9a). Reaction of 5a with R‘NC gives trans-[Pd{C(O)C6H4OH-2}I(CNR‘)2] (R‘ = Xy (10a),tBu (10a*)), which, in turn, react with further R‘NC in the presence of Tl(OTf) to give [Pd{C(O)C6H4OH-2}(CNR‘)3]OTf (R‘ = Xy (11a), tBu (11a*)). Finally, the reaction of 7a withPd(OAc)2 results in the tetrameric [Pd{κ2(C,O)-μ2(O)-C(NXy)C6H4O-2}(CNXy)]4 (12) andtrans-[PdI2(CNXy)2]. Most of the reported aroyl (4−6, 10, 11) and iminoaroyl (7−9, 12)derivatives are new types of palladium complexes. The crystal structures of complexes 5a,7a, 7b, 8b, 9a, and 12 have been determined by X-ray diffraction methods. The followingscale of trans influence has been established: bpy < I < C(NXy)C6H4OC(O)Me-2 ≈C(O)C6H4OH-2 < C(NXy)C6H4OH-2.
- Oxidative addition reactions of 2-ROC6H4I (R = H, C(O)Me, C(O)CHCH2) with Pd(dba)2 in the presence of the appropriate ligand results in the formation of the first ortho-palladated phenol derivatives. Reactions of these complexes with carbon monoxide yield insertion products and, with isonitriles, complexes resulting after insertion or/and substitution reactions. The complex trans-[Pd{C(NXy)C6H4OH-2}I(CNXy)2] (Xy = 2,6-dimethylphenyl) reacts with Pd(OAc)2 to give the tetrameric [Pd{κ2(C,O)-μ2(O)-C(NXy)C6H4O-2}(CNXy)]4.
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