5 H. Yoshida, T. Terayama, J. Ohshita and A. Kunai, Chem. Commun.,
2004, 1980.
6 H. Yoshida, E. Shirakawa, Y. Honda and T. Hiyama, Angew. Chem.,
Int. Ed., 2002, 41, 3247.
We thank Central Glass Co. Ltd. for a generous gift of
trifluoromethanesulfonic anhydride.
Hiroto Yoshida,* Takashi Minabe, Joji Ohshita and Atsutaka Kunai*
Department of Applied Chemistry, Graduate School of Engineering,
Hiroshima University, Higashi-Hiroshima 739-8527, Japan.
E-mail: yhiroto@hiroshima-u.ac.jp; akunai@hiroshima-u.ac.jp;
Fax: +81-82-424-5494; Tel: +81-82-424-7724
7 Y. Himeshima, T. Sonoda and H. Kobayashi, Chem. Lett., 1983, 1211.
8 The reactions with longer reaction times occasionally resulted in lower
yields. At present, the relationship between the yields and the reaction
times is unclear, since the aminosilylation products did not decompose
under the reaction conditions even with the prolonged reaction times.
9 For reviews on the nucleophilic couplings with arynes, see: S. V. Kessar,
in Comprehensive Organic Synthesis, ed. B. M. Trost and I. Flemming,
Pergamon Press, Oxford, 1991, vol. 4, pp. 483–515; H. Pellissier and
M. Santelli, Tetrahedron, 2003, 59, 701.
10 For reported examples of the nucleophilic couplings of amines with
arynes, see: Z. Liu and R. C. Larock, Org. Lett., 2003, 5, 4673; Z. Liu
and R. C. Larock, Org. Lett., 2004, 6, 3739.
11 Alternatively, the observed regioselectivity can also be explained by
polarization of the triple bond of 4-fluorobenzyne induced by the fluoro
substituent.
Notes and references
1 Se–Se and Te–Te s-bond: N. Petragnani and V. G. Toscano, Chem.
Ber., 1970, 103, 1652; S–S s-bond: J. Nakayama, T. Tajiri and
M. Hoshino, Bull. Chem. Soc. Jpn., 1986, 59, 2907; C–Si s-bond:
Y. Sato, Y. Kobayashi, M. Sugiura and H. Shirai, J. Org. Chem., 1978,
43, 199; Sn–Cl s-bond: C.-L. Tseng, S.-H. Tung and K.-M. Chang,
Chem. Abstr., 1964, 61, 7035; B–O s-bond: C.-L. Tseng, K.-M. Chang
and S.-H. Tung, Chem. Abstr., 1964, 61, 16084.
12 Similar regioselectivities were observed in the three-component coupling
of arynes, isocyanides and aldehydes: H. Yoshida, H. Fukushima,
J. Ohshita and A. Kunai, Angew. Chem., Int. Ed., 2004, 43, 3935.
13 As a referee commented, the charge density of an aryne in the ground
state should be dependent on the substituent, and affect the reactivity of
the aryne. However, the yields of the reactions using substituted arynes
varied widely from high to low irrespective of the electron-donating
or -withdrawing character of the substituents.
2 H. Yoshida, Y. Honda, E. Shirakawa and T. Hiyama, Chem. Commun.,
2001, 1880.
3 H. Yoshida, J. Ikadai, M. Shudo, J. Ohshita and A. Kunai, J. Am.
Chem. Soc., 2003, 125, 6638; H. Yoshida, J. Ikadai, M. Shudo,
J. Ohshita and A. Kunai, Organometallics, 2005, 24, 156; J. Ikadai,
H. Yoshida, J. Ohshita and A. Kunai, Chem. Lett., 2005, 34, 56.
4 H. Yoshida, K. Tanino, J. Ohshita and A. Kunai, Angew. Chem., Int.
Ed., 2004, 43, 5052.
3456 | Chem. Commun., 2005, 3454–3456
This journal is ß The Royal Society of Chemistry 2005