abstract
The syntheses of (Bn(2)Cyclam)Zr(NMe(2))(2) (1), (Bn(2)Cyclam)Zr(NH(2,6-Me)Ph)Cl (2) and (Bn(2)Cyclam)Zr(N(2,6-Me)Ph) (3) are described. The reactivity of 1, 3, (Bn(2)Cyclam)Zr(CH(2)Ph)(2) (4) and ((C(6)H(4)CH(2))(2)Cyclam)Zr (5) as hydroamination catalysts of aminoalkenes is reported. High conversions of the primary gem-disubstituted aminoalkenes in 5- or 6-member ring N-heterocycles were observed. Reactions of 1, 4 and 5 with CH(2) = CHCH(2)CPh(2)CH(2)NH(2) gave (Bn(2)Cyclam)Zr(NHR)(2) (6) (R = CH(2)CPh(2)CH(2)CH = CH(2)) that on heating converts sequentially into the mono-ortho-metallated species ((C(6)H(4)CH(2))BnCyclam)Zr(NHR) (7) and the bis-ortho-metallated ((C(6)H(4)CH(2))(2)Cyclam)Zr (5), simultaneously with the hydroamination product. (C) 2010 Elsevier B.V. All rights reserved.
keywords
INTERMOLECULAR HYDROAMINATION; ASYMMETRIC HYDROAMINATION; ALKENE HYDROAMINATION; AMIDATE COMPLEXES; IMIDO COMPLEXES; ALKYNES; PRECATALYST; REACTIVITY; TITANIUM; LIGANDS
subject category
Chemistry
authors
Antunes, MA; Munha, RF; Alves, LG; Schafer, LL; Martins, AM
our authors
Rui Munhá
Post-doc FellowshipGroups
acknowledgements
The authors would like to thank to Fundacao para a Ciencia e a Tecnologia, Portugal, for funding (PTDC/QUI/66187/2006; SFRH/BPD/26745/2006; SFRH/BD/29986/2006; SFRH/BD/44295/2008) and to the Portuguese NMR Network (IST-UTL Centre) for providing access to the NMR facility. We would also like to thank the Schafer group members Ms. Philippa R. Payne and Dr. Patricia Horrillo Martinez for providing the substrates and guidance on the catalytic reactions.