Synthesis of tetraaryl-p-benzoquinones and 2,3-diaryl-1,4-naphthoquinones via SuzukieMiyaura cross-coupling reactions Zahid Hassan a, f , Ihsan Ullah a, b , Iftikhar Ali a, c , Rasheed Ahmad Khera a, d , Ingo Knepper a , Asad Ali a, b , Tam  as Patonay e , Alexander Villinger a , Peter Langer a, f, * a Institut f€ ur Chemie, Universit€ at Rostock, Albert Einstein Str. 3a, 18059 Rostock, Germany b Department of Chemistry, Abdul Wali Khan University, Mardan, KPK, Pakistan c Department of Chemistry, Karakoram International University, Gilgit-Baltistan, Pakistan d University of Agriculture, Faisalabad, Punjab, Pakistan e Department of Organic Chemistry, University of Debrecen, 4032 Debrecen, Egyetem t er 1, Hungary f Leibniz-Institut f€ ur Katalyse an der Universit€ at Rostock e.V., Albert Einstein Str. 29a, 18059 Rostock, Germany article info Article history: Received 28 June 2012 Received in revised form 25 October 2012 Accepted 8 November 2012 Available online xxx Keywords: Catalysis Palladium Benzoquinone SuzukieMiyaura reaction Naphthalene abstract The palladium-catalyzed SuzukieMiyaura coupling reaction of tetrabromo-p-benzoquinone and 2,3- dibromonaphthoquinone provide a convenient approach to tetraaryl-p-benzoquinones and 2,3- diarylnaphthoquinones. SuzukieMiyaura of tetrabromo-1,4-phenylene bis(trifluoromethanesulfonate) and of 2,3-dibromonaphthalene-1,4-diyl bis(trifluoromethanesulfonate) resulted in the formation of the same type of quinone products instead of the expected benzene and naphthalene derivatives. Ó 2012 Elsevier Ltd. All rights reserved. 1. Introduction Polysubstituted quinones are widely distributed in pharmaco- logically relevant natural products found in plants, fungi, and bac- teria. Thi s privileged core structure possesses electron and proton transfer properties, which are essential to nearly all living organ- isms. 1 Therefore, quinones play an important role in chemistry, material science, nanotechnology, and medicine. 2 They occur in several natural products, 2b including sesquiterpenes, 3 the kin- amycins, 4 terphenylquinones, 5 and also occur in drugs and thera- peutic lead structures. 6 Pharmacologically relevant natural products include both p-benzoquinones and p-dihy- drobenzoquinones. 7 Examples include sorrentanone 8 and a-toco- pherolquinone. 9 Terphenylquinones are also found in nature and show activity against human protein tyrosine kinase (e.g., A and B, Fig. 1). 10 2-(5-Oxohexa-1,3-dienyl)-1,4-naphthoquinone (C), which was isolated from the insect pathogenic fungus Cordyceps unilat- eralis, shows anti-malarial activity. 11 The trimeric naphthoquinone derivative conocurvone (D) was isolated from Conospermum sp. and has attracted the attention of the scientific community because of its anti-HIV activity. 12 The conocurvone relevant quinone model systems were later on synthesized by coupling of naphthopyranyl stannanes to hydroxy quinone triflates using standard Stille cou- pling conditions. 13 Quinone-based triarylphosphine derivatives are potential candidates for functional materials, such as photo- conductors for electrophotography. 14 Molina et al. have reported the direct arylation of benzo-fused 1,4-quinones by Pd(II)-catalyzed addition reactions of arylboronic acids. 15 These reactions show a high regioselectivity when non- symmetrical quinones were used, due to the presence of sub- stituents in the benzene moiety of the starting materials. 16 Reactions of tetrabromo- and tetrachlorobenzoquinones with amines, 17 thiols, 18 Grignard reagents, 19 malodinitrile, 20 alkyne carbanions, 21 indole 22 and S,S-, N,S-, and N,O-dinucleophiles, 23 and [4þ2] cycloadditions have been previously reported. 24 Tetraaryl-p-benzoquinones have been previously prepared by reaction of phenyldiazonium salts with tetrabromoquinone 25 and by oxidation of 2,3,5,6-tetraarylphenols. 26 Tetrachloro-p-benzo- quinone has also been reported to induce dehydrogenation reactions. 27 Palladium-catalyzed SuzukieMiyaura cross-coupling reactions of polyhalogenated substrates provide an excellent methodology * Corresponding author. E-mail address: peter.langer@uni-rostock.de (P. Langer). Contents lists available at SciVerse ScienceDirect Tetrahedron journal homepage: www.elsevier.com/locate/tet 0040-4020/$ e see front matter Ó 2012 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.tet.2012.11.040 Tetrahedron xxx (2012) 1e10 Please cite this article inpress as: Hassan, Z.; et al., Tetrahedron (2012), http://dx.doi.org/10.1016/j.tet.2012.11.040