Efficient and Copper-Free Pd(OAc)₂/DABCO-Catalyzed Sonogashira Cross-Coupling Reaction

Abstract

An efficient and copper-free palladium-catalyzed Sonogashira cross-coupling reaction protocol is presented. In the presence of 3 mol% of Pd(OAc)₂ and 6 mol% of DABCO, cross-coupling of various aryl halides (iodides and bromides) with terminal alkynes afforded the corresponding alkynes in moderate to excellent­ yields. Moreover, high TONs (turnover numbers, up to 720 000 for the reaction of 1-iodo-4-nitrobenzene with phenylacetylene) for the Sonogashira cross-coupling reaction were observed.

Key words

Pd(OAc)₂/DABCO - Sonogashira cross-coupling reaction - aryl halide - terminal alkyne - turnover number

References

• 1a Diederich F. Stang PJ. Metal-Catalyzed Cross-coupling Reactions   Wiley-VCH; Weinheim: 1998. 
• 1b Miyaura N. Cross-Coupling Reaction   Springer; Berlin: 2002. 
• 1c Negishi E. Handbook of Organopalladium Chemistry for Organic Synthesis   Wiley-Interscience; New York: 2002. 
• 1d Tykwinski RR. Angew. Chem. Int. Ed.  2003,  42:  1566 
• 1e Tang S. Liang Y. Liu W.-J. Li J.-H. Chin. J. Org. Chem.  2004,  24:  1133 
• 2a Viehe HG. Chemistry of Acetylene   Marcel Dekker; New York: 1969.  p.597 
• 2b Bohlmann F. Burkhart FT. Zero C. Naturally Occurring Acetylenes   Academic Press; London and New York: 1973. 
• 2c Trahanovsky WS. Oxidation in Organic Chemistry   Academic Press; New York: 1973. 
• 2d Hansen L. Boll PM. Phytochem.  1986,  25:  285 
• 2e Kim YS. Jin SH. Kim SL. Hahn DR. Arch. Pharm. Res.  1989,  12:  207 
• 2f Matsunaga H. Katano M. Yamamoto H. Fujito H. Mori M. Tukata K. Chem. Pharm. Bull.  1990,  38:  3480 
• 2g Hudlicky M. Oxidation in Organic Chemistry   ACS Monograph 186; Washington DC: 1990.  p.58 
• 2h Sonogashira K. In Comprehensive Organic Synthesis   Vol. 3:  Trost BM. Fleming I. Pergamon; Oxford: 1991.  p.551 
• 2i Alonso F. Beletskaya IP. Yus M. Chem. Rev.  2004,  104:  3079 
• For recent representative papers on phosphine-palladium catalysts, see:
• 3a Böhm VPW. Herrmann WA. Eur. J. Org. Chem.  2000,  3679 
• 3b Netherton MR. Fu GC. Org. Lett.  2001,  3:  4295 
• 3c Méry D. Heuzé K. Astrc D. Chem. Commun.  2003,  1934 
• 3d Gelman D. Buthwald SL. Angew. Chem. Int. Ed.  2003,  42:  5993 
• 3e Elangovan A. Wang Y.-H. Ho T.-I. Org. Lett.  2003,  5:  1841 
• 3f Feuerstein M. Berthiol F. Doucet H. Santelli M. Synthesis  2004,  1281 ; and references cited therein
• 3g Wolf C. Lerebours R. Org. Biomol. Chem.  2004,  2:  2161 
• 3h Hierso J.-C. Fihri A. Amardeil R. Meunier P. Doucet H. Santelli M. Ivanov VV. Org. Lett.  2004,  6:  3473 
• 3i Heuzé K. Méry D. Gauss D. Blais J.-C. Astruc D. Chem.-Eur. J.  2004,  10:  3936 
• 3j Cheng J. Sun Y. Wang F. Guo M. Xu J.-H. Pan Y. Zhang Z. J. Org. Chem.  2004,  69:  5428 
• 3k Feuerstein M. Doucet H. Santelli M. Tetrahedron Lett.  2004,  45:  8443 
• 3l Adjabeng G. Brenstrum T. Frampton CS. Robertson AJ. Hillhouse J. McNulty J. Capretta A. J. Org. Chem.  2004,  69:  5082 
• 3m Arques A. Aunon D. Molina P. Tetrahedron Lett.  2004,  45:  4337 
• For recent representative papers on other phosphine-free ligand-palladium catalysts, see:
• 4a Loch JA. Albrecht M. Peris E. Mata J. Faller JW. Crabtree RH. Organometallics  2002,  21:  700 
• 4b Herrmann WA. Angew. Chem. Int. Ed.  2002,  41:  1290 
• 4c Batey RA. Shen M. Lough AJ. Org. Lett.  2002,  4:  1411 
• 4d Eckhardt M. Fu GC. J. Am. Chem. Soc.  2003,  125:  13642 
• 4e Yong BS. Nolan SP. Chemtracts: Org. Chem.  2003,  205 
• 4f Rau S. Lamm K. Goerls H. Schoeffel J. Walther D. J. Organomet. Chem.  2004,  689:  3582 
• 4g Gossage RA. Jenkins HA. Yadav PN. Tetrahedron Lett.  2004,  45:  7689 
• 4h Alonso DA. Botella L. Najera C. Pacheco MC. Synthesis  2004,  1713 
• 4i Thakur VV. Kumar NSCR. Sudalai A. Tetrahedron Lett.  2004,  45:  2915 
• For recent representative papers on ligand-free palladium catalysts, see:
• 5a Alami M. Ferri F. Linstrumelle G. Tetrahedron Lett.  1993,  34:  6403 
• 5b Heidenreich RG. Kohler K. Krauter JGE. Pietsch J. Synlett  2002,  1118 
• 5c Urgaonkar S. Verkade JG. J. Org. Chem.  2004,  69:  5752 ; and references cited therein
• 5d Son SU. Jang Y. Park J. Na HB. Park HM. Yun HJ. Lee J. Hyeon T. J. Am. Chem. Soc.  2004,  126:  5026 
• 6a Homogeneous Catalysis with Metal Phosphine Complexes   Pignolet LH. Plenum; New York: 1983. 
• 6b Parshall GW. Ittel S. Homogeneous Catalysis   Wiley; New York: 1992. 
• 7 Siemsen P. Livingston RC. Diederich F. Angew. Chem. Int. Ed.  2000,  39:  2632 
• 8 Li J.-H. Liu W.-J. Org. Lett.  2004,  6:  2809 
• Among the tertiary amines, only HMPA is bulkier than DABCO. In the coupling transformation, although bulk favors reductive elimination, it impedes oxidative addition and transmetalation of substrates allowed by the more flexible ligand, see:
• 9a Strieter ER. Blackmond DG. Buchwald SL. J. Am. Chem. Soc.  2003,  125:  13978 
• 9b See also: Altenhoff G. Goddard R. Lehmann CW. Glorius F. Angew. Chem. Int. Ed.  2003,  42:  3690 
• 9c Tao B. Boykin DW. J. Org. Chem.  2004,  69:  4330 
• 10 Arques A. Auñon A. Molina P. Tetrahedron Lett.  2004,  45:  4337 ; and references cited therein