490 (1270), 340 (1560); (MeOH) 600 (940), 330 (1670); (THF) 490
the Government of Newfoundland and Labrador for funding. We
are grateful to Prof. Francesca M. Kerton for use of the GC-
MS instrument, acquired through a CFI Leaders Opportunity
Fund Award. The Bruker AvanceIII-300 NMR spectrometer was
acquired through NSERC Research Tools and Instruments and
Newfoundland Research Development Corporation grants. X. Q.
thanks the Memorial University of Newfoundland School of
Graduate Studies for funding.
(2030), 330 (2330). meff (solution, 25 ◦C) 5.8 mB per mol Fe.
Cross-coupling catalysis.
Method A. Procedure for cross-coupling at room temperature:
Catalyst 1 (50 mg, 0.05 mmol of 1 or 0.1 mmol formula units
of [FeL1Cl]) in CH2Cl2 (3 mL) was added to a 45 mL Radleys
Carousel Reactor tube and the solvent removed in vacuo. To the
catalyst were added Et2O (5 mL), alkyl halide (2.0 mmol) and
an ether solution of aryl Grignard reagent (4.0 mmol) was added
dropwise under vigorous stirring (except for entries 11 to 15 where
8.00 mmol of Grignard was used). The resulting mixture was
stirred for 30 min, then dodecane (2.0 mmol as internal standard)
was added and the reaction quenched with 5 mL 1.0 M HCl(aq).
The organic phase was extracted with Et2O (5 mL) and dried over
MgSO4. The mixture was analyzed by GC-MS and NMR. NMR
samples were preparedbycarefulremovalof solventunder vacuum
and dissolving the residue in CDCl3. Method B. Procedure for
cross-coupling under microwave-heating: In a glove box, complex
1 (50 mg, 0.1 mmol of [FeClL1]) and a magnetic stir bar were
added to a BiotageTM microwave vial, which was sealed with a
septum cap. A solution of alkyl halide (2.00 mmol) in Et2O was
injected into the vial, followed by 4.00 mmol of Grignard reagent in
Et2O (except for entry 14 where 8.00 mmol of Grignard was used).
The mixture was heated in a Biotage InitiatorTM Eight Microwave
Synthesizer using the following parameters: time = 10 min; T =
100 ◦C; prestirring = off; absorption level = high; fixed hold time =
on. Upon completion, 2.00 mmol of dodecane (internal standard)
was added to the mixture followed by 5.0 mL of 1.0 M HCl(aq) to
quench. The product yields were quantified by GC-MS (relative
to standard curves) and in several cases by 1H NMR.
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38
were included in Fcalc
;
the values for Df¢ and Df¢¢ were those
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of Creagh and McAuley.39 The values for the mass attenuation
coefficients are those of Creagh and Hubbell.40 All calculations
were performed using the CrystalStructure41 crystallographic
software package except for refinement, which was performed
using SHELXL-97.42 Crystallographic data (excluding structure
factors) for compounds 1–4 have been deposited at the Cambridge
Crystallographic Data Centre. CCDC reference numbers 776031
(1), 793580 (2), 793581 (3), 793582 (4).†
Acknowledgements
C. M. K. thanks Memorial University of Newfoundland, the
Natural Sciences and Engineering Research Council (NSERC)
of Canada, the Canada Foundation for Innovation (CFI) and
25 For a related ligand see: A. J. Chmura, M. G. Davidson, M. D. Jones,
M. D. Lunn and M. F. Mahon, Dalton Trans., 2006, 887.
942 | Dalton Trans., 2011, 40, 933–943
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