5296
M. Bieniek et al. / Journal of Organometallic Chemistry 691 (2006) 5289–5297
(
(
(
s), 1446 (m), 1420 (m), 1308 (m), 1259 (s), 1155 (m), 1125
s), 1083 (s), 967 (w), 935 (m), 851 (w), 817 (w), 724 (w), 699
m), 602 (s), 534 (m).
vent was evaporated and the residue was dissolved in
minimal amount of CH Cl . The catalyst was precipitated
with cold n-pentane. The crude 7a was purified by column
chromatography (0–20% ethyl acetate/c-hexane). The cata-
lyst 7a was obtained as a green solid. The product 11b–d
was formed in quantitative yield (purity >98% by GC).
2
2
4
.4. Preparation of precatalyst 7b
Precursor 6 (44.9 mg; 0.11 mmol), CuCl (27.3 mg;
0
.27 mmol) and CH Cl (10 mL) were placed in a Schlenk
4.7. Catalytic RCM of diene 12 with catalysts 1c, 1e, 7a and 7b
2
2
flask. Afterwards carbene complex 1a (194.2 mg;
.23 mmol) was added and the resulted solution was stirred
0
Diene 12 (7.5 mmol) was dissolved in degassed toluene
(554 mL) and placed in a reaction flask under nitrogen.
The solution was heated to 80 ꢁC and the first portion of
catalyst 1c, 1e, 7a and 7b (0.4 mol% Ru) was added to
the stirred solution as a solid. After stirring at this temper-
ature for 60 min. the second amount of the catalyst
(0.2 mol% Ru) was added and the solution was stirred
for another 60 min. Progress of the reaction was followed
by HPLC.
under argon at 40 ꢁC for 30 min. From this point forth, all
manipulations were carried out in air with reagent-grade
solvents. The reaction mixture was concentrated under vac-
uum and the resulted material was purified by column
chromatography on silica. Elution with c-hexane:AcOEt
(
9:1) removes first 7a as a green band and afterwards 7b
as a green band as well. The solvent was evaporated and
each of two fractions was dissolved in a small amount
CH Cl , then MeOH was added and slowly evaporated
2
2
until green crystals precipitated. The precipitate was fil-
tered off, washed with n-pentane and dried in vacuo to
afford complex 7a (19.2 mg, 21%) as green crystals and
Acknowledgements
Research support by the Polish Academy of Sciences
the main product 7b (94.3 mg, 66%) as green crystals. Com-
(President of Polish Academy of Sciences Fellowship to
1
plex 7b: H NMR (500 MHz, CDCl ): d 1.26 (d,
3
M.B.) is gratefully acknowledged. This paper was written
while K.G. was on sabbatical leave at the University of
Dortmund, with support from the Alexander von Hum-
boldt Foundation. We wish to thank Prof. Dr. Jerzy Wicha
3
JHH = 6.0 Hz, 12H, CH ), 2.41 (bs, 12H, ArCH ), 2.46
3
3
(
bs, 24H, ArCH3), 4.19 (s, 8H, CH2); 4.93 (k,
3
3
JHH = 6.0 Hz, 2H, C CH), 6.87 (d, J = 8.7 Hz, 2H,
2
HH
Ar–H), 7.07 (s, 8H, Ar–H), 7.52 (s, 2H, Ar–H), 7.87 (d,
(IOC PAS) for granting access to the GC apparatus, which
3
13
JHH = 8.7 Hz, 2H, Ar–H), 16.41 (s, 2H, CH); C NMR
125 MHz, CDCl ): d 19.3, 21.0, 21.1, 51.5, 113.5, 121.4,
speeded up our work considerably and to Dr. Tomasz
Kowalczyk for numerous inspiring discussions.
(
3
1
28.7, 129.5, 135.4, 139.1, 144.5, 155.2, 209.1, 292.0
(
C@Ru); MS (ESI (+); MeOH/CH Cl ) the molecular for-
2
2
Appendix A. Supplementary data
mula was confirmed by comparing the theoretical and
experimental
(
+
isotope
patterns
for
[M]
ion
C H Cl N O Ru S) found to be identical within the
6
2
74
4
4
4
2
ꢀ1
experimental error limits; IR (film, cm ); m 3444 (m),
2
1
7
917 (m), 1606 (w), 1572 (m), 1480 (s), 1420 (s), 1398 (s),
262 (s), 1131 (s), 1086 (s), 939 (m), 916 (m), 852 (m),
23 (w), 702 (m), 613 (m), 589 (s), 532 (w).
References
[
[
1] D. Astruc, New J. Chem. 29 (2005) 42.
2] R.H. Grubbs (Ed.), Handbook of Metathesis, vols. 1–3, Wiley-VCH,
Weinheim, 2003.
4
.5. Catalytic RCM of 10a with 7a and 7b
[
[
[
3] A. F u¨ rstner, Angew. Chem. 112 (2000) 3140.
4] T.M. Trnka, R.H. Grubbs, Acc. Chem. Res. 34 (2001) 18.
5] V. Dragutan, I. Dragutan, A.T. Balaban, Platinum Met. Rev. 45
To a solution of catalyst 7a or 7b (0.01–0.005 mmol,
1
.0–0.5 mol%) in CH Cl (40 ml) in a Schlenk tube a solu-
2
2
tion of diene 10a (1.0 mmol) was introduced in CH Cl
2
2
(
2001) 155.
(
2
5 ml) and the reaction mixture was stirred for 5 h at
6 ± 2 ꢁC under argon. Progress of the reaction was fol-
[
[
6] J.A. Love, J.P. Morgan, T.M. Trnka, R.H. Grubbs, Angew. Chem.,
Int. Ed. 41 (2002) 4035.
7] (a) J.S. Kingsbury, J.P.A. Harrity, P.J. Bonitatebus, A.H. Hoveyda,
J. Am. Chem. Soc. 121 (1999) 791;
lowed by TLC and GC. Conversions were calculated by
GC, using n-nonane as an internal standard.
(
b) S.B. Garber, J.S. Kingsbury, B.L. Gray, A.H. Hoveyda, J. Am.
Chem. Soc. 122 (2000) 8168.
4
.6. General procedure for recycling of the catalyst 7a
[
8] For a review on precatalysts 1c, 1d and its variations, see A.H.
Hoveyda, D.G. Gillingham, J.J. Van Veldhuizen, O. Kataoka, S.B.
Garber, J.S. Kingsbury, J.P.A. Harrity, Org. Biomol. Chem. 2 (2004) 1.
9] S. Gessler, S. Randl, S. Blechert, Tetrahedron Lett. 2000 (2000) 9973.
The catalyst 7a (0.025 mmol, 2.5 mol%) was placed in a
[
Schlenk tube. The tube was filled with argon and CH Cl
2
2
[
10] K. Grela, S. Harutyunyan, A. Michrowska, Angew. Chem., Int. Ed.
(
40 mL) was added. To this a solution of the substrate
4
1 (2002) 4038.
1
0b–d (1.0 mmol) in CH Cl (5 mL) was added. The result-
2 2
[11] A. Michrowska, R. Bujok, S. Harutyunyan, V. Sashuk, G. Dolgonos,
K. Grela, J. Am. Chem. Soc. 126 (2004) 9318.
ing solution was stirred at 20 or 0 ꢁC for 0.3–2 h. The sol-