We thank Dr. B. N. Jagatap for encouragement of this work.
The author (P.M) is thankful to the Department of Atomic
Energy-Mumbai University Collaborative Scheme for providing
junior research fellowship.
Table 5
Effect of catalyst loading on heck reactiona
catalyst 1, 120 oC
Ar
+
Ar Br
Entry ArBr
R
R
DMA, NaOAc
R
Pd
Yield
(%)
100
81
TON
Supplementary Data
mol%
0.4
Experimental procedure for aryl bromide and butyl acrylate,
preparation of palladium complexes and spectral data of products
are provided in supplementary material.
1
4-CH3COC6H4Br
4-CH3COC6H4Br
Ph
250
2
Ph
0.2
405
3
4-CH3COC6H4Br
4-CH3COC6H4Br
4-CH3COC6H4Br
2-OHCC6H4Br
2-OHCC6H4Br
4-OHCC6H4Br
4-OHCC6H4Br
4-CH3COC6H4Br
4-CH3COC6H4Br
4-CH3COC6H4Br
4-CH3COC6H4Br
4-CH3COC6H4Br
1-C10H7Br
Ph
0.02
0.002
0.0002
0.4
100b
90b
82b
99
5000
45000
410000
248
References and notes
4
Ph
5
Ph
1. (a) Heck, R. F. Comprehensive Organic Synthesis, B. M. Trost and I.
Fleming (Eds.), Pergamon Press, Oxford, 1991, vol. 4, p. 833; (b)
Oestreich, M. The Mizoroki-Heck Reaction, John Wiley & Sons, 2009.
2. Johansson Seechurn, C. C. C.; Kitching, M. O.; Colacot, T. J.; Snieckus,
V. Angew. Chem. Int. Ed. 2012, 51, 50625085.
6
Ph
7
Ph
0.2
92
460
8
Ph
0.4
98
245
3. Wolfe, J. P.; Singer, R. A.; Yang, B. H.; Buchwald, S. L. J. Am. Chem.
9
Ph
0.2
90
450
Soc. 1999, 121, 95509561.
4. Stambuli, J. P.; Kuwano, R.; Hartwig, J. F. Angew. Chem. Int. Ed. 2002,
41, 47464748.
10
11
12
13
14
15
16
CO2Bun
CO2Bun
CO2Bun
CO2Bun
CO2Bun
CO2Bun
CO2Bun
0.4
100b
97b
96b
95b
50b
85c
31c
250
0.2
485
5. Kim, J. -H.; Kim, J. -W.; Shokouhimehr, M.; Lee, Y. -S. J. Org. Chem.
0.02
0.002
0.0002
0.4
4800
47500
250000
213
2005, 70, 67146720.
6. Roland, S.; Mangeney, P.; Jutand, A. Synlett. 2006, 308894.
7. Farina, V. Adv. Synth. Catal. 2004, 346, 15531582.
8. Herrera-Alvarez, C.; Gomez-Benitez, G.; Redon, R.; Garcia, J.;
Hernandez-Ortega, S.; Toscano, R. A.; Morales-Morales, D. J.
Organomet. Chem. 2004, 689, 246472.
1-C10H7Br
0.04
775
9. Chen, W.; Li, R.; Han, B.; Li, B-J.; Chen, Y-C.; Wu, Y.; Ding, L-S. and
a
Yang, D. Eur. J. Org. Chem. 2006, 117784.
Reaction conditions: Aryl bromide (1.0 mmol), alkene (1.5 mmol), NaOAc
10. (a) Paluru, D. K.; Dey, S.; Wadawale, A. and Jain, V. K. J. Organomet.
Chem., 2013, 728, 5256; (b) Khairnar, B. J.; Dey, S.; Jain, V. K.;
Bhanage, B. M. Tetrahedron Lett., 2014, 55, 716719.; (c) Paluru, D. K.;
Dey, S.; Chaudhari, K. R.; Khedkar, M. V.; Bhanage, B. M. and Jain, V.
K. Tetrahedron Lett., 2014, 55, 29532956.
in H2O (2 mmol for styrene and 1.5 mmol for butyl acrylate reaction), time
(16 hrs for styrene and 18 hrs for butyl acrylate reaction), DMA (3 mL), 120
°C. b TBAB (1 mmol) added. c TBAB (3 mmol) added.
11. Wang, H.; Zhong, R.; Guo, X.-Q.; Feng, X.-Y.; Hou, X.-F. Eur. J. Inorg.
larger octanuclear complex 3 is more stable than tetranuclear
complexes 1 and 2, as calculated by the DFT computational
studies. It may facilitates the formation of catalytically active
species slightly more in case of tetranuclear complexes and
enhanced the activity. It may be noted that the NCN- or SCS-
pincer complexes of lower stability showed higher effective
concentrations of catalytically active species than the higher
stable PCP-pincer complexes.1b
Chem. 2010 174178.
12. Dervisi, A.; Koursarou, D.; Ooi, L-l.; Horton, P. N.; Hurthouse, M. B.
Dalton Trans. 2006, 57175724.
13. Jones, R. C.; Canty, A. J.; Gardiner, M. G.; Skelton, B. W.; Tolhurst, V-
A.; White, A. H. Inorg. Chim. Acta 2010, 363, 7787.
14. Singh, P.; Das, D.; Prakash, O.; Singh, A. K. Inorg. Chim. Acta 2013,
394, 7784
15. Kostas, I.D.; Steele, B.R.; Terzis, A.; Amosova, S.V.; Martynov, A.V.;
Makhaeva, N.A. Eur. J. Inorg. Chem. 2006, 26422646.
16. (a) Yuan, D.; Huynh, H. V. Organometallics 2010, 29, 60206027; (b)
Fliedel, C.; Braunstein, P. Organometallics 2010, 29, 56145626.
17. Zim, D.; Gruber, A. S.; Ebeling, G.; Dupont, J.; Monteiro, A. L. Org.
Lett. 2000, 2, 28812884.
Moreover, experiments were carried out to assess the
reusability of the catalyst. After the reaction of styrene and 4-
bromoacetophenone, ethyl acetate was added to the product
mixture resulting in the formation of two layers. The upper layer
of ethyl acetate, containing the product was removed to give
100% yield. The catalyst 1 containing lower aqueous layer was
then employed for another reaction, accordingly proportional
amount of reactants were further added. After 16 h the first
reaction cycle resulted 90% yield, repeating the similar process
the second and third reaction cycles yielded 78 and 66% of the
products. The results showed that the catalyst remains active with
a slight loss of activity after three successive cycles.
18. Wang, W-C.; Peng, K-F.; Chen, M-T. and Chen, C-T. Dalton Trans.
2012, 41, 30223029.
19. Bergbreiter, D. E.; Osburn, P. L.; Liu, Y. S. J. Am. Chem. Soc. 1999,
121, 9531.
20. Bai, S-Q. and Andy Hor, T. S. Chem. Commun. 2008, 31723174.
21. Yao, Q.; Kinney, E.P.; Zheng, C. Org. Lett. 2004, 6, 29972999.
22. (a) Chakraborty, T.; Srivastava, K.; Singh, H.B.; Butcher, R.J. J.
Organomet. Chem. 2011, 696, 25592564; (b) Ghavale, N.; Manjare, S.
T.; Singh, H.B.; Butcher, R.J. Dalton Trans. 2015, 44, 1189311900.
23. (a) Rao, G.K.; Kumar, A.; Ahmed, J.; Singh, A.K. Chem. Commun.
2010, 46, 59545956; (b) Rao, G.K.; Kumar, A.; Kumar, B.; Kumar, D.;
Singh, A.K. Dalton Trans. 2012, 41, 19311937.
In summary, we have demonstrated that the supramolecular
palladium dithiolate complexes can catalyse the Heck coupling
reactions for a wide range of aryl bromides. These results clearly
proves once again that sulfur ligands, can promote CC bond
forming reactions, rather being treated as catalyst poison. A
dramatic increase in activities was observed on addition of
TBAB. Under optimized conditions and low catalyst loading, the
complex can show excellent catalytic activity with high turnover
number (TON = 410000) and turnover frequency (TOF = 25625
h1).
24. Vivekananda, K. V.; Dey, S.; Wadawale, A.; Bhuvanesh, N.; Jain, V. K.
Dalton Trans. 2013, 42, 1415814167.
25. Paluru, D. K.; Dey, S.; Wadawale, A.; Maity, D. K.; Bhuvanesh, N.; Jain,
V. K. Eur. J. Inorg. Chem. 2015, 397407.
26. Dunleavy, J. K. Platinum Met. Rev. 2006, 50, 110.
27. Vanjari, R.; Guntreddi, T.; Kumar, S.; Singh, K. N. Chem. Commun.
2015, 51, 366369.
28. Ananikov, V. P.; Orlov, N. V.; Beletskaya, L. P.; Khrustalev, V. N.;
Antipin, M. Yu.; Timofeeva, T. V. J. Am. Chem. Soc. 2007, 129,
72527253.
30. Lu, C. –H. and Chang, F. –C. ACS Catal. 2011, 1, 481488.
31. Vivekananda, K. V.; Dey, S.; Maity, D. K.; Bhuvanesh, N.; Jain, V. K.
Inorg. Chem. 2015, 54, 1015310162.
Acknowledgments