Regioselective Synthesis of Substituted Imidate N-[1-Methyleneisobenzofuran-3(1H)-ylidene]benzenamines via Palladium-Catalyzed Tandem Heteroannulation of o-(1-Alkynyl)benzamides with Iodobenzene

Abstract

A variety of substituted imidate N-[1-methyleneisobenzofuran-3(1H)-ylidene]benzenamines have been prepared in good to excellent yields by the palladium-catalyzed tandem heteroannulation of o-(1-alkynyl)benzamides with iodobenzene. The products obtained from this process were unusual substituted N-[isobenzo­furan-3(1H)-ylidene]benzenamines. The tandem cyclization of readily available o-(1-alkynyl)benzamides and aryl iodides provided a powerful tool for the preparation of functionally substituted N-[isobenzofuran-3(1H)-ylidene]benzenamine compounds.

isobenzofuran - o-(1-alkynyl)benzamide - iodobenzene - tandem - palladium catalysis

References and Notes

1a Tietze LF. Chem. Rev.  1996,  96:  115 

1b Malacria M. Chem. Rev.  1996,  96:  289 

1c Ikeda S.-I. Acc. Chem. Res.  2000,  33:  511 

1d Battistuzzi G. Cacchi S. Fabrizi G. Eur. J. Org. Chem.  2002,  2671 

1e Balme G. Bossharth E. Monteiro N. Eur. J. Org. Chem.  2003,  4101 

1f Luo F.-T. Wang R.-T. Tetrahedron Lett.  1991,  32:  7703 

1g Oh CH. Lim YM. Tetrahedron Lett.  2003,  44:  2670 

2a Ha Y.-H. Kang S.-K. Org. Lett.  2002,  4:  1143 

2b Ohno H. Miyamura K. Takeoka Y. Tanaka T. Angew. Chem. Int. Ed.  2003,  42:  2647 

2c Kneisel FF. Dochnahl M. Knochel P. Angew. Chem. Int. Ed.  2004,  43:  1017 

2d Kressierer CJ. Müller TJJ. Angew. Chem. Int. Ed.  2004,  43:  5997 

2e Zhu G. Zhang Z. Org. Lett.  2004,  6:  4041 

2f Zhu G. Tong X. Cheng J. Sun Y. Li D. Zhang Z. J. Org. Chem.  2005,  70:  1712 

2g Pinto A. Neuville L. Retailleau P. Zhu J. Org. Lett.  2006,  8:  4927 

2h Ishikura M. Takahashi N. Yamada K. Yanada R. Tetrahedron  2006,  62:  11580 

3a Larock RC. J. Organomet. Chem.  1999,  576:  111 

3b Nakamura I. Yamamoto Y. Chem. Rev.  2004,  104:  2127 

3c Zeni G. Larock RC. Chem. Rev.  2004,  104:  2285 

3d Alonso F. Beletskaya IP. Yus M. Chem. Rev.  2004,  104:  3079 

3e Cacchi S. Fabrizi G. Chem. Rev.  2005,  105:  2873 

3f Zeni G. Larock RC. Chem. Rev.  2006,  106:  4644 

4a Madin A. O’Donnell CJ. Oh T. Old DW. Overman LE. Sharp MJ. Angew. Chem. Int. Ed.  1999,  38:  2934 

4b Hynes J. Overman LE. Nasser T. Rucker PV. Tetrahedron Lett.  1998,  39:  4647 

4c Hong CY. Overman LE. Romero A. Tetrahedron Lett.  1997,  38:  8439 

4d Wu GG. Wong YS. Poirier M. Org. Lett.  1999,  1:  745 

4e Smith GB. Dezeny GC. Hughes DL. King AO. Verhoeven TR. J. Org. Chem.  1994,  59:  8151 

5a Pedrosa R. Sayalero S. Vicente M. Tetrahedron  2006,  62:  10400 

5b Zhu XZ. Li X.-Y. Liu J. Eur. J. Pharmacol.  2004,  500:  221 

5c Rao YS. Chem. Rev.  1976,  76:  625 

5d Mukhopadhyay R. Kundu NG. Tetrahedron  2001,  57:  9475 

6a Baldwin JE. Bair KW. Tetrahedron Lett.  1978,  19:  2559 

6b Kim KS. Spatz MW. Johnson F. Tetrahedron Lett.  1979,  20:  331 

6c Pahari P. Senapati B. Mal D. Tetrahedron Lett.  2004,  45:  5109 

6d Mal D. Pahari P. De S R. Tetrahedron  2007,  63:  11781 

7a Landge SM. Berryman M. Török B. Tetrahedron Lett.  2008,  49:  4505 

7b Paradkar MV. Gadre SY. Pujari TA. Khandekar PP. Kumbhar VB. Synth. Commun.  2005,  35:  471 

8a Brotherton TK. Lynn JW. Chem. Rev.  1959,  59:  841 

8b Roger R. Neilson DG. Chem. Rev.  1961,  61:  179 

9a Grossman RB. Rasne RM. Org. Lett.  2001,  3:  4027 

9b Hamada Y. Hara O. Kawai A. Kohno Y. Shioiri T. Tetrahedron  1991,  47:  8635 

10a Bundgaard H. Larsen JD. J. Med. Chem.  1988,  31:  2066 

10b Kini GD. Robins RK. Avery TL. J. Med. Chem.  1989,  32:  1447 

11a Pinner A. Klein F. Ber. Dtsch. Chem. Ges.  1877,  10:  1889 

11b Pinner A. Klein F. Ber. Dtsch. Chem. Ges.  1878,  11:  1475 

11c Pinner A. Ber. Dtsch. Chem. Ges.  1883,  16:  1643 

12 Kochi T. Ellman JA. J. Am. Chem. Soc.  2004,  126:  15652 

13 Restituyo JA. Comstock LR. Petersen SG. Stringfellow T. Rajski SR. Org. Lett.  2003,  5:  4357 

14 Schaefer FC. Peters GA. J. Org. Chem.  1961,  26:  412 

15a Yoo EJ. Bae I. Cho SH. Han H. Chang S. Org. Lett.  2006,  8:  1347 

15b Yoo EJ. Ahlquist M. Bae I. Sharpless KB. Fokin VV. Chang S. J. Org. Chem.  2008,  73:  5520 

16a Saluste CG. Crumpler S. Furber M. Whitby RJ. Tetrahedron Lett.  2004,  45:  6995 

16b Fernandez-Rivas C. Cardenas DJ. Martin-Matute B. Monge A. Gutierrez-Puebla E. Echavarren AM. Organometallics  2001,  20:  2998 

17a Yoshida H. Fukushima H. Ohshita J. Kunai A. Angew. Chem. Int. Ed.  2004,  43:  3935 

17b Yoshida H. Fukushima H. Morishita T. Ohshita J. Kunai A. Tetrahedron  2007,  63:  4793 

18 Yao T. Larock RC. J. Org. Chem.  2005,  70:  1432 

19 Xie Y.-X. Yan Z.-Y. Wang D.-Z. Wu L.-Y. Qian B. Liu X.-Y. Liang Y.-M. Eur. J. Org. Chem.  2009,  2283 

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General Procedure for the Preparation of N -[Isobenzo-furan-1 (3 H )-ylidene]benzenamine Compounds To a solution of o-(1-alkynyl)benzamides 1 (0.50 mmol) in MeCN (3.0 mL) was added 2,6-lutidine (1.00 mmol). The mixture was stirred for 10 min and Pd(PPh₃)₄ (5 mol%) and organic halides (0.60 mmol) were added. The resulting mixture was then heated under an argon atmosphere at refluxing temperature. When the reaction was considered complete, as determined by TLC analysis, the reaction mixture was cooled to r.t., quenched with a sat. aq solution of NH₄Cl, and extracted with EtOAc. The combined organic extracts were washed with H₂O and sat. brine. The organic layers were dried over Na₂SO₄ and filtered. The solvents were evaporated under reduced pressure. The residue was purified by chromatography on silica gel to afford the corresponding N-[1-(diphenylmethylene)isobenzofuran-3 (1H)-ylidene]benzenamine. Thus, starting with 1a (149 mg, 0.5 mmol) and iodobenzene 2a (122 mg, 0.6mmol), a yellowish solid product 4aa (273 mg, 73%) was isolated; mp 173-175 ˚C. ^¹H NMR (300 MHz, CDCl₃): δ = 6.24 (d, J = 8.0 Hz, 1 H), 7.14-7.29 (m, 5 H), 7.35-7.41 (m, 5 H), 7.48-7.52 (m, 7 H), 8.00 (d, J = 7.6 Hz, 1 H). ^¹³C NMR (75 MHz, CDCl₃): δ = 120.77, 123.27, 123.42, 124.02, 124.76, 127.50, 127.86, 128.38, 128.59, 129.24, 129.26, 129.86, 130.66, 130.82, 131.68, 136.67, 137.80, 137.90, 145.64, 145.77, 153.98. IR (neat): 3052, 2923, 1681, 1013, 755, 693 cm^-¹. Anal. Calcd for C₂₇H₁₉NO: C, 86.84; H, 5.13; N, 3.75; O, 4.28. Found: C, 86.70; H, 5.06; N, 3.73; O, 4.35.

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The atomic coordinates for 4ac have been deposited at the Cambridge Crystallographic Data Centre (deposition number: CCDC 800275). The coordinates can be obtained on request from the Director Cambridge Crystallographic Data Centre. Postal Address: 12 Union Road, Cambridge CB2 1EZ, UK; Email: [e-mail]; fax: [phone]; tel.: [phone].

22a Guo L.-N. Duan X.-H. Bi H.-P. Liu X.-Y. Liang Y.-M. J. Org. Chem.  2006,  71:  3325 

22b Duan X.-H. Guo L.-N. Bi H.-P. Liu X.-Y. Liang Y.-M. Org. Lett.  2006,  8:  3053 

22c Bossharth E. Desbordes P. Monteiro N. Balme G. Org. Lett.  2003,  5:  2441 

22d Dai G. Larock RC. Org. Lett.  2001,  3:  4035 

22e Dai G. Larock RC. J. Org. Chem.  2003,  68:  920