310
O. Volkov, P. Paetzold / Journal of Organometallic Chemistry 680 (2003) 301ꢃ311
/
Five non-equivalent resonance structures can be
drawn for the ni-11BV structure of the hypothetical
(C ; 7 BBB and 6 BB bonds; Fig. 12). Five
References
/
ꢀ
/
4
11
ꢀ
[1] M.F. Hawthorne, D.C. Young, T.D. Andrews, D.V. Howe, R.L.
Pilling, A.D. Pitts, M. Reintjes, L.F. Warren, Jr., P.A. Wegner, J.
Am. Chem. Soc. 90 (1968) 879.
B H
1
1
5v
equivalent structures can be generated from each of the
symmetric formulae (a)ꢃ(c) by applying the C opera-
/
5
[2] P. Paetzold, U. Englert, H.-P. Hansen, F. Meyer, E. Leuschner, Z.
Anorg. Allg. Chem. 627 (2001) 498.
tions and ten equivalent structures from each of the
unsymmetrical formulae (d) and (e) by applying all the
symmetry operations of C , giving a total amount of 35
[
[
3] R.E. Williams, Chem. Rev. 92 (1992) 177.
4] V.D. Aftandilian, H.C. Miller, G.W. Parshall, E.L. Muetterties,
Inorg. Chem. 4 (1962) 734.
5
v
resonance structures.
The valence structures of B H
[
5] D.F. Gaines, A.N. Bridges, R.K. Hayashi, Inorg. Chem. 33 (1994)
2
11
ꢀ
4ꢀ
and B H
in
12 are built up from BH vertices only. Valence
1243.
[6] N.S. Hosmane, J.R. Wermer, Z. Hong, T.D. Getman, S.G. Shore,
Inorg. Chem. 26 (1987) 3638.
1
1
11 11
Figs. 10ꢃ
/
structures, that include BHB bridges, can easily be
generated from the given structures by adding one or
more protons to appropriate 2c2e bonds with formation
of BHB 3c2e bonds. Appropriate for the generation of
[
[
[
7] G.B. Dunks, K. Palmer-Ordonez, Inorg. Chem. 17 (1978)
514.
1
8] G.B. Dunks, K. Barker, E. Hedaya, C. Hefner, K. Palmer-
Ordonez, P. Remec, Inorg. Chem. 20 (1981) 1692.
9] T.D. Getman, J.A. Krause, S.G. Shore, Inorg. Chem. 27 (1988)
ꢀ
ꢂ
the cl-11BV
to the 2c2e bond B2ꢀ
the 16 resonance structures of Fig. 11. Appropriate for
/
Iꢀ
/
structure of B H is the addition of H
11 12
2
398.
/B4, which is present in 14 out of
[
[
10] P. Maitre, O. Eisenstein, D. Michos, X.L. Luo, A.R. Siedle, L.
Wisnieski, K.W. Zilm, R.H. Crabtree, J. Am. Chem. Soc. 115
(1993) 7747.
3
ꢀ
2ꢀ
the generation of valence structures of B H , B H
11 13
,
1
1
12
ꢀ
14
11] L.J. Edwards, J.M. Makhlouf, J. Am. Chem. Soc. 88 (1966)
4728.
B H , and B H are the structures of Fig. 12: (a)ꢃ
/(e)
1
1
11 15
3
ꢀ
2ꢀ
for B H , (a)ꢃ(e) for B H , (a), (b), (d), (e) for
/
1
1
12
11 13
[
[
12] K. Radacki, O. Volkov, P. Paetzold, unpublished results.
13] C.J. Fritchie, Inorg. Chem. 6 (1967) 1199.
ꢀ
14
B H , and (a), (d), (e) for B H .
1
1
11 15
Valence structures, which include endo-BH bonds,
can be derived from the corresponding bridged struc-
[14] W. Dirk, P. Paetzold, K. Radacki, Z. Anorg. Allg. Chem. 627
(2001) 2615.
[15] D.L. Keller, J.G. Kester, J.C. Huffman, L.J. Todd, Inorg. Chem.
ꢀ
14
tures. Let us start, e.g. from a B H structure with
1
1
3
2 (1993) 5067.
three BHB bridges and transform this structure into one
with two non-adjacent BHB bridges and one endo-BH
bond, which is the real ground-state structure. The tri-
bridged structure of Fig. 13 is derived from structure (d)
of Fig. 12 by adding three protons, thus transforming
[
[
16] F. Klanberg, E.L. Muetterties, Inorg. Chem. 5 (1966) 1955.
17] O. Volkov, W. Dirk, U. Englert, P. Paetzold, Z. Anorg. Allg.
Chem. 625 (1999) 1193.
[
[
18] W. Dirk, P. Paetzold, unpublished results.
19] G.D. Friesen, J.L. Little, J.C. Huffman, L.J. Todd, Inorg. Chem.
1
8 (1979) 755.
4
ꢀ
the hypothetical B H
into a non-ground state
structure of B H . The transformation into the
1
ꢀ
14
1
11
[20] W.R. Pretzer, R.W. Rudolph, J. Am. Chem. Soc. 98 (1976) 1441.
[21] A. Franken, B.T. King, J. Rudolph, P. Rao, B.C. Noll, J. Michl,
Collect. Czech. Chem. Comm. 66 (2001) 1238.
1
1
ground-state structure involves the transformations of
a BHB into a BH and of a BB into a BBB bond. Such
elementary reactions are frequently found in boron
hydride chemistry. More generally, the transformation
of a 3c2e into a 2c2e and, simultaneously, of a 2c2e into
a 3c2e bond have been called a [3c, 2c]-translocation
[
22] O. Volkov, K. Radacki, P. Paetzold, X. Zheng, Z. Anorg. Allg.
Chem. 627 (2001) 1185.
[23] E.F. Tolpin, W.N. Lipscomb, J. Am. Chem. Soc. 95 (1973) 2384.
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12 (1990) 2597.
26] R. Rousseau, S. Lee, J. Chem. Phys. 101 (1994) 10753.
(
[
[
1
[
48]. Our simple localizing orbital description is certainly
not suitable to compare the energy of the two isomers of
Fig. 13.
[27] E.L. Muetterties, E.L. Hoel, C.G. Salentine, M.F. Hawthorne,
Inorg. Chem. 14 (1975) 950.
[
[
28] R.B. King, Inorg. Chim. Acta 49 (1981) 237.
29] O. Volkov, P. Paetzold, C. Hu, U. K o¨ lle, Z. Anorg. Allg. Chem.
6
27 (2001) 1029.
[30] N.S. Hosmane, A. Franken, G. Zhang, R.Y. Srivastava, R.Y.
Smith, B.F. Spielvogel, Main Group Met. Chem. 21 (1998)
3
19.
[
[
31] E.H. Wong, M.G. Gatter, Inorg. Chim. Acta 61 (1982) 95.
32] E.H. Wong, L. Prasad, E.J. Gabe, M.G. Gatter, Inorg. Chem. 22
(
1983) 1143.
[
[
33] M. M u¨ ller, P. Paetzold, Coord. Chem. Rev. 176 (1998) 135.
34] A. Ouassas, B. Fenet, H. Mongeot, B. Gautheron, E. Barday, B.
Frange, J. Chem. Soc. Chem. Commun. (1995) 1663.
[35] P. Paetzold, P. Lomme, U. Englert, Z. Anorg. Allg. Chem. 628
(
2002) 632.
Fig. 13. Transformation of a BHBꢀ
/
3c2e into a BHꢀ
/2c2e bond by a
[36] B.P. Sullivan, R.N. Leyden, M.F. Hawthorne, J. Am. Chem. Soc.
ꢀ
14
[
3c,2c]-translocation with nido-B11
H
.
97 (1975) 455.