Bipodal surface organometallic complexes with surface N-donor ligands and application to the catalytic cleavage of C-H and C-C bonds in n -Butane
Anjum, Dalaver H.
Pasha, Fahran A.
KAUST DepartmentChemical Science Program
Homogeneous Catalysis Laboratory (HCL)
Imaging and Characterization Core Lab
KAUST Catalysis Center (KCC)
Physical Science and Engineering (PSE) Division
Online Publication Date2013-11-14
Print Publication Date2013-11-27
Permanent link to this recordhttp://hdl.handle.net/10754/563108
MetadataShow full item record
AbstractWe present a new generation of "true vicinal" functions well-distributed on the inner surface of SBA15: [(Sî - Si-NH 2)(≡Si-OH)] (1) and [(≡Si-NH2)2] (2). From these amine-modified SBA15s, two new well-defined surface organometallic species [(≡Si-NH-)(≡Si-O-)]Zr(CH2tBu) 2 (3) and [(≡Si-NH-)2]Zr(CH2tBu) 2 (4) have been obtained by reaction with Zr(CH2tBu) 4. The surfaces were characterized with 2D multiple-quantum 1H-1H NMR and infrared spectroscopies. Energy-filtered transmission electron microscopy (EFTEM), mass balance, and elemental analysis unambiguously proved that Zr(CH2tBu)4 reacts with these vicinal amine-modified surfaces to give mainly bipodal bis(neopentyl)zirconium complexes (3) and (4), uniformly distributed in the channels of SBA15. (3) and (4) react with hydrogen to give the homologous hydrides (5) and (6). Hydrogenolysis of n-butane catalyzed by these hydrides was carried out at low temperature (100 C) and low pressure (1 atm). While (6) exhibits a bis(silylamido)zirconium bishydride, [(≡Si-NH-)2]Zr(H) 2 (6a) (60%), and a bis(silylamido)silyloxozirconium monohydride, [(≡Si-NH-)2(≡Si-O-)]ZrH (6b) (40%), (5) displays a new surface organometallic complex characterized by an 1H NMR signal at 14.46 ppm. The latter is assigned to a (silylimido)(silyloxo)zirconium monohydride, [(≡Si-Nî)(≡Si-O-)]ZrH (5b) (30%), coexistent with a (silylamido)(silyloxo)zirconium bishydride, [(≡Si-NH-)(≡Si-O-)] Zr(H)2 (5a) (45%), and a silylamidobis(silyloxo)zirconium monohydride, [(≡Si-NH-)(≡Si-O-)2]ZrH (5c) (25%). Surprisingly, nitrogen surface ligands possess catalytic properties already encountered with silicon oxide surfaces, but interestingly, catalyst (5) with chelating [N,O] shows better activity than (6) with chelating [N,N]. © 2013 American Chemical Society.
SponsorsWe gratefully acknowledge the financial support of King Abdullah University of Science and Technology as well as Prof. Kazuhiro Takanabe and Dr. Gregory Biausque for their help in the ammonia treatments and the EFTEM experiments, respectively.
PublisherAmerican Chemical Society (ACS)
- CO2 activation through silylimido and silylamido zirconium hydrides supported on N-donor chelating SBA15 surface ligands.
- Authors: Pasha FA, Bendjeriou-Sedjerari A, Abou-Hamad E, Huang KW, Basset JM
- Issue date: 2016 Feb 11
- Molecular understanding of the formation of surface zirconium hydrides upon thermal treatment under hydrogen of [([triple bond]SiO)Zr(CH2tBu)3] by using advanced solid-state NMR techniques.
- Authors: Rataboul F, Baudouin A, Thieuleux C, Veyre L, Copéret C, Thivolle-Cazat J, Basset JM, Lesage A, Emsley L
- Issue date: 2004 Oct 6
- Tungsten(VI) Carbyne/Bis(carbene) Tautomerization Enabled by N-Donor SBA15 Surface Ligands: A Solid-State NMR and DFT Study.
- Authors: Bendjeriou-Sedjerari A, Sofack-Kreutzer J, Minenkov Y, Abou-Hamad E, Hamzaoui B, Werghi B, Anjum DH, Cavallo L, Huang KW, Basset JM
- Issue date: 2016 Sep 5
- Synergy between Two Metal Catalysts: A Highly Active Silica-Supported Bimetallic W/Zr Catalyst for Metathesis of n-Decane.
- Authors: Samantaray MK, Dey R, Kavitake S, Abou-Hamad E, Bendjeriou-Sedjerari A, Hamieh A, Basset JM
- Issue date: 2016 Jul 13
- Zr(IV)-monosubstituted Keggin-type dimeric polyoxometalates: synthesis, characterization, catalysis of H2O2-based oxidations, and theoretical study.
- Authors: Kholdeeva OA, Maksimov GM, Maksimovskaya RI, Vanina MP, Trubitsina TA, Naumov DY, Kolesov BA, Antonova NS, Carbó JJ, Poblet JM
- Issue date: 2006 Sep 4