dimeric constitution by analogy to the known gallium oxide and
sulfide species, [HC{(Me)C(2,6-iPr2C6H3)}2GaE]2 (E = O or S).12
We are continuing to sudy the reactivity of these, and related,
well defined In(I) species.
We would like to thank the Royal Society for a University
Research Fellowship (MSH) and Mr Peter Haycock for assistance
with the diffusion NMR measurements.
Notes and references
† Selected analytical data; 8: mp 175 ◦C. Elemental analysis: C42H50In2N4:
calcd C 60.02, H 6.00, N 6.67; found C 60.12, H 6.00, N 6.57%; 1H NMR
(500 MHz, C6D6, 25 ◦C): d = 1.58 (s, 6H, CMe), 2.11 (s, 12H, o-Me),
1
4.88 (s, 1H, CH), 6.95 (m, 2H, p-ArH), 7.08 (d, 4H, m-Ar). 13C{ H}
(100.6 MHz, C6D6) d = 24.2 (m-Me), 28.4 (CMe), 102.9 (c-CH), 129.4
(ArH), 133.0 (ArH), 133.9 (ArH), 142.3 (i-Ar), 153.4 (CN). 12: Elemental
analysis: C63H75In3N6O3: calcd C 57.76, H 5.73, N 6.42; found C 57.78, H
6.68, N 6.36%; 1H NMR (270 MHz, C6D6, 25 ◦C): d = 1.54 (s, 6H, CMe),
2.13 (s, 12H, o-Me), 4.81 (s, 1H, CH), 6.97–7.08 (m, 6H, m,p-ArH).
‡ Crystal data: 173 K, Nonius Kappa CCD diffractometer, k(Mo Ka) =
Fig. 3 DOSY spectrum of a 1 : 1 : 1 mixture of compounds 6 (red), 7
(blue) and 8 (black).
¯
˚
0.71073 A. 8: C42H50In2N4, M = 840.50, triclinic, P1 (No. 2), a = 8.6989(5),
˚
b = 10.0246(6), c = 12.3181(7) A, a = 67.338(3), b = 82.783(3), c =
◦
3
83.862(3) , V = 981.38(10) A , Z = 1, l = 1.21 mm−1, 7198 collected
˚
reflections, 3420 independent reflections [R(int) = 0.045], R indices [I >
2r(I)] R1 = 0.033, wR2 = 0.073, [all data] R1 = 0.041, wR2 = 0.076. 12:
C63H75In3N6O3, M = 1308.75, monoclinic, P21/n◦(No. 14), a = 13.9231(3),
3
˚
˚
b = 34.7614(10), c = 14.0230(3) A, b = 118.27(3) , V = 5977.3(3) A , Z =
4, l = 1.20 mm−1, 24282 collected reflections, 8154 independent reflections
[R(int) = 0.049], R indices [I > 2r(I)] R1 = 0.051, wR2 = 0.096, [all
data] R1 = 0.078, wR1 = 0.106. CCDC reference numbers 625827 and
625828. For crystallographic data in CIF or other electronic format see
DOI: 10.1039/b616747k
1 Review: P. P. Power, Chem. Rev., 1999, 99, 3463.
2 (a) M. S. Hill and P. B. Hitchcock, Chem. Commun., 2004, 1818;
(b) M. S. Hill, P. B. Hitchcock and R. Pongtavornpinyo, Dalton Trans.,
2005, 1433.
3 M. S. Hill, P. B. Hitchcock and R. Pongtavornpinyo, Angew. Chem.,
2005, 44, 1433.
4 M. S. Hill, P. B. Hitchcock and R. Pongtavornpinyo, Science, 2006,
311, 1904.
5 For example: (a) W. Uhl, A. Janschak, W. Saak, M. Kaupp and R.
Wartchow, Organometallics, 1998, 17, 5009; (b) N. J. Hardman, R. J.
Wright, A. D. Phillips and P. P. Power, Angew. Chem., Int. Ed., 2002,
41, 2842; (c) R. J. Wright, A. D. Phillips, N. J. Hardman and P. P. Power,
J. Am. Chem. Soc., 2002, 124, 8538 and references therein.
6 C.-H. Chen, M.-L. Tsai and M.-D. Su, Organometallics, 2006, 25, 2766.
7 P. Pyykko¨, Chem. Rev., 1997, 97, 597.
8 H. Schmidbaur, S. Cronje, B. Djordjevic and O. Schuster, Chem. Phys.,
2005, 311, 151.
9 P. Pyykko¨, M. Straka and T. Tamm, Phys. Chem. Chem. Phys., 1999,
1, 3441.
Fig.
4
ORTEP diagram of 12 (20% probability ellipsoids). H
˚
atoms omitted for clarity. Selected bond lengths [A] and angles
[◦]: In(1)–O(1) 2.014(4), In(1)–O(3) 1.977(5), In(1)–N(1) 2.188(5),
In(1)–N(2) 2.179(5), In(2)–O(1) 1.998(4), In(2)–O(2) 1.999(5), In(2)–N(3)
2.163(5), In(2)–N(4) 2.169(6), In(3)–O(2) 1.972(5), In(3)–O(3) 2.006(5),
In(3)–N(5) 2.187(5), In(3)–N(6) 2.163(5); N(1)–In(1)–N(2) 87.9(2),
O(1)–In(1)–O(3) 116.77(19), N(3)–In(2)–N(4) 87.8(2), O(1)–In(2)–O(2)
117.5(2), N(5)–In(3)–N(6) 87.7(2), O(2)–In(3)–O(3) 117.7(2).
10 P. S. Pregosin, P. G. Anil Kumar and I. Fernndez, Chem. Rev., 2005,
105, 2977.
11 M. J. Frisch, G. W. Trucks, H. B. Schlegel, G. E. Scuseria, M. A.
Robb, J. R. Cheeseman, J. A. Montgomery, Jr., T. Vreven, K. N.
Kudin, J. C. Burant, J. M. Millam, S. S. Iyengar, J. Tomasi, V. Barone,
B. Mennucci, M. Cossi, G. Scalmani, N. Rega, G. A. Petersson, H.
Nakatsuji, M. Hada, M. Ehara, K. Toyota, R. Fukuda, J. Hasegawa,
M. Ishida, T. Nakajima, Y. Honda, O. Kitao, H. Nakai, M. Klene, X.
Li, J. E. Knox, H. P. Hratchian, J. B. Cross, C. Adamo, J. Jaramillo,
R. Gomperts, R. E. Stratmann, O. Yazyev, A. J. Austin, R. Cammi,
C. Pomelli, J. W. Ochterski, P. Y. Ayala, K. Morokuma, G. A. Voth,
P. Salvador, J. J. Dannenberg, V. G. Zakrzewski, S. Dapprich, A. D.
Daniels, M. C. Strain, O. Farkas, D. K. Malick, A. D. Rabuck, K.
Raghavachari, J. B. Foresman, J. V. Ortiz, Q. Cui, A. G. Baboul, S.
Clifford, J. Cioslowski, B. B. Stefanov, G. Liu, A. Liashenko, P. Piskorz,
I. Komaromi, R. L. Martin, D. J. Fox, T. Keith, M. A. Al-Laham, C. Y.
Peng, A. Nanayakkara, M. Challacombe, P. M. W. Gill, B. Johnson, W.
Chen, M. W. Wong, C. Gonzalez and J. A. Pople, Gaussian 03, Revision
C.02, Gaussian, Inc., Wallingford, CT, 2004.
Although we are continuing to explore the oxidative reaction
chemistry of the In(I) compounds, 6–8, the monomeric and
‘carbene-like’ formulation of all three species in hydrocarbon
solution indicates that this reactivity will almost certainly exclude
‘olefin-like’ addition chemistry (i.e. with maintenance of an In–
In interaction) for compounds 7 and 8. Indeed, any divergence
of reactivity of 6, 7 or 8 with oxidising reagents is likely to be
solely a result of kinetic factors and the differing steric demands
of the supporting ligands. For example, a hexane solution of the
o-xylyl substituted complex 8, rapidly decolourises when exposed
to air and deposits the trimeric indium oxide, 12, (Fig. 4)‡ as the
only reaction product. Although the outcome of a similar reaction
of the more sterically hindered compound 6 has not yet yielded
a definitive result, it is likely that the indium oxide will have a
12 N. J. Hardman and P. P. Power, Inorg. Chem., 2001, 40, 2474.
This journal is
The Royal Society of Chemistry 2007
Dalton Trans., 2007, 731–733 | 733
©