Competitive Insertion of Isocyanide into Tantalum−Amido and Tantalum−Methyl Bonds

✍ Scribed by Francisco Amor; Javier Sánchez-Nieves; Pascual Royo; Heiko Jacobsen; Olivier Blacque; Heinz Berke; Maurizio Lanfranchi; Maria Angela Pellinghelli; Antonio Tiripicchio

• Publisher: John Wiley and Sons
• Year: 2002
• Tongue: English
• Weight: 181 KB
• Volume: 2002
• Category: Article
• ISSN: 1434-1948
• DOI: 10.1002/1099-0682(200211)2002:11<2810::aid-ejic2810>3.0.co;2-c

✦ Synopsis

The (amido)methyl complexes [Ta(η 5 -C 5 Me 5 )(NtBu)-Me(NR 2 )] [R = Ph (3), SiMe 3 (4)] were prepared by reaction of [Ta(η 5 -C 5 Me 5 )(NtBu)ClMe] (1) with the appropriate lithium amides. Attempts to isolate the analogous NHMe derivative afforded a mixture of complexes [Ta(η 5 -C 5 Me 5 )(NtBu)-Me(NHMe)] ( 5) and [Ta(η 5 -C 5 Me 5 )(NMe)Me(NHtBu)] ( 6), resulting from hydrogen exchange between the amido and imido ligands. Insertion of CN(2,6-Me 2 C 6 H 3 ) into the Ta-Me bond of complexes 3 and 4 gave the η 1 -iminoacyl derivatives [Ta(η 5 -C 5 Me 5 )(NtBu)(NR 2 ){η 1 -C(Me)=N(2,6-Me 2 C 6 H 3 )}] [R = Ph (7), SiMe 3 (8)], while insertion into the Ta-NRMe (R = H,