Platinum(II) Chloride Catalyzed Cycloisomerizations of 1,5-Enynes

Abstract

1,5-Enynes are highly reactive under PtCl₂ catalysis and give a range of [3.1.0] bicyclic skeletons. The scope and limitations of this process are presented. Regioisomeric keto derivatives are obtained depending upon the nature of the oxygenated substituent at the propargylic position of the starting substrate.

Key words

enynes - platinum - bicyclic compounds - carbenes - cycloisomerizations

References

• 1 Trost BM. Lautens M. J. Am. Chem. Soc.  1985,  107:  1781 
• 2a Aubert C. Buisine O. Malacria M. Chem. Rev.  2002,  102:  813 
• 2b Malacria M. Goddard JP. Fensterbank L. In Comprehensive Organometallic Chemistry III   Vol. 10:  Crabtree R. Mingos M. Ojima I. Pergamon Press; Oxford: 2006.  Chap. 7. p.299-368  
• For a pioneering report with Pd(II), see:
• 3a Trost BM. Tanoury GH. J. Am. Chem. Soc.  1988,  110:  1636 
• 3b See also: Trost BM. Hashmi ASK. Angew. Chem., Int. Ed. Engl.  1993,  32:  1085 
• For a pioneering report with PtCl₂, see:
• 4a Chatani N. Morimoto T. Muto T. Murai S. J. Am. Chem. Soc.  1994,  116:  6049 
• See also:
• 4b Fürstner A. Stelzer F. Szillat H. J. Am. Chem. Soc.  2001,  123:  11863 
• 4c Méndez M. Muñoz MP. Nevado C. Cárdenas DJ. Echavarren AM. J. Am. Chem. Soc.  2001,  123:  10511 
• 4d Méndez M. Mamane V. Fürstner A. Chemtracts: Org. Chem.  2003,  16:  397 
• 4e Fensterbank L. PtCl₂, In e-EROS - Encyclopedia of Reagents for Organic Synthesis [Online]   Wiley; New York: 2006. 
• 4f For the first report of asymmetric synthesis, see: Charruault L. Michelet V. Taras R. Gladiali S. Genêt J.-P. Chem. Commun.  2004,  850 
• For reviews, see:
• 5a Jiménez-Núñez E. Echavarren AM. Chem. Commun.  2007,  333 
• 5b Ma S. Yu S. Gu Z. Angew. Chem. Int. Ed.  2006,  45:  200 
• 5c Hashmi ASK. Gold Bull.  2004,  37:  51 
• 5d Bruneau C. Angew. Chem. Int. Ed.  2005,  44:  2328 
• 5e Zhang L. Sun J. Kozmin SA. Adv. Synth. Catal.  2006,  348:  2271 
• 6a Oi S. Tsukamoto I. Miyano S. Inoue Y. Organometallics  2001,  20:  3704 
• 6b For a review, see: Diver ST. Giessert AJ. Chem. Rev.  2004,  104:  1317 
• 6c For a theoretical treatment, see: Nieto-Oberhuber C. Lopez S. Muñoz MP. Cárdenas DJ. Buñuel E. Nevado C. Echavarren AM. Angew. Chem. Int. Ed.  2005,  44:  6146 
• An illustration of this is the use of ynamides, see:
• 7a Marion F. Coulomb J. Courillon C. Fensterbank L. Malacria M. Org. Lett.  2004,  6:  1509 
• 7b For gold catalysis, see: Couty S. Meyer C. Cossy J. Angew. Chem. Int. Ed.  2006,  45:  6726 
• 7c For trapping of a charged intermediate, see: Lemière G. Gandon V. Agenet N. Goddard J.-P. de Kozak A. Aubert C. Fensterbank L. Malacria M. Angew. Chem. Int. Ed.  2006,  45:  7596 
• 8a Mainetti E. Mouriès V. Fensterbank L. Malacria M. Marco-Contelles J. Angew. Chem. Int. Ed.  2002,  41:  2132 
• 8b Cariou K. Mainetti E. Fensterbank L. Malacria M. Tetrahedron  2004,  60:  9745 
• 8c Harrak Y. Blaszykowski C. Bernard M. Cariou K. Mainetti E. Mouriès V. Dhimane AL. Fensterbank L. Malacria M. J. Am. Chem. Soc.  2004,  126:  8656 
• 8d Marco-Contelles J. Arroyo N. Anjum S. Mainetti E. Marion N. Cariou K. Lemière G. Mouriès V. Fensterbank L. Malacria M. Eur. J. Org. Chem.  2006,  4618 
• 8e Cariou K. Ronan B. Mignani S. Fensterbank L. Malacria M. Angew. Chem. Int. Ed.  2007,  46:  1881 
• For earlier reports, see:
• 9a Strickler H. Davis JB. Ohloff G. Helv. Chim. Acta  1976,  59:  1328 
• 9b Rautenstrauch V. J. Org. Chem.  1984,  49:  950 
• For platinum-catalyzed 1,2-migration, see:
• 10a Mamane V. Gress T. Krause H. Fürstner A. J. Am. Chem. Soc.  2004,  126:  8654 
• 10b Anjum S. Marco-Contelles J. Tetrahedron  2005,  61:  4793 
• 10c Pujanauski BG. Prasad BAB. Sarpong R. J. Am. Chem. Soc.  2006,  128:  6786 
• 10d For a review, see: Marco-Contelles J. Soriano E. Chem. Eur. J.  2007,  13:  1350 
• 10e For a theoretical study, see: Soriano E. Ballesteros P. Marco-Contelles J. Organometallics  2005,  24:  3182 
• For gold-catalyzed 1,2-migration, see:
• 11a Review: Marion N. Nolan SP. Angew. Chem. Int. Ed.  2007,  46:  2750 
• 11b See also: Marion N. de Frémont P. Lemière G. Stevens ED. Fensterbank L. Malacria M. Nolan SP. Chem. Commun.  2006,  2048 
• For asymmetric transformations, see:
• 11c Shi X. Gorin DJ. Toste FD. J. Am. Chem. Soc.  2005,  127:  5802 
• 11d Johansson MJ. Gorin DJ. Staben ST. Toste FD. J. Am. Chem. Soc.  2005,  127:  18002 
• 11e For ruthenium catalysis, see: Miki K. Ohe K. Uemura S. J. Org. Chem.  2003,  68:  8505 
• 11f Tenaglia A. Marc S. J. Org. Chem.  2006,  71:  3569 
• 12a Fürstner A. Hannen P. Chem. Commun.  2004,  2546 
• 12b Fürstner A. Hannen P. Chem. Eur. J.  2006,  12:  3006 
• 12c Fehr C. Galindo J. Angew. Chem. Int. Ed.  2006,  45:  2901 
• 12d

  See also ref. 10b.

• 13 Blaszykowski C. Harrak Y. Gonçalves M.-H. Cloarec J.-M. Dhimane AL. Fensterbank L. Malacria M. Org. Lett.  2004,  6:  3771 
• See refs. 10a, 12b and 12c. For gold-catalyzed studies on 1,5-enyne substrates, see for instance:
• 14a Sun J. Conley MP. Zhang L. Kozmin SA. J. Am. Chem. Soc.  2006,  128:  9705 
• 14b Luzung MR. Markham JP. Toste FD. J. Am. Chem. Soc.  2004,  126:  10858 
• 14c Gagosz F. Org. Lett.  2005,  7:  4129 
• 14d For copper catalysis, see: Fehr C. Farris I. Sommer H. Org. Lett.  2006,  8:  1839 
• 15 Parsons PJ. Willis PJ. Eyley SC. Tetrahedron  1992,  48:  9461 
• 16a Nakai T. Mikami K. Chem. Rev.  1986,  86:  885 
• 16b Journet M. Malacria M. J. Org. Chem.  1992,  57:  3085 
• 18 Soriano E. Marco-Contelles J. J. Org. Chem.  2007,  72:  2651 
• 19 Hours AE. Snyder JK. Tetrahedron Lett.  2006,  47:  675 
• 20 For another recent synthesis of Sabinaketone, see: Hodgson DM. Chung YK. Paris J.-M. J. Am. Chem. Soc.  2004,  126:  8664 
• 21 Barberis M. Pérez-Prieto J. Tetrahedron Lett.  2003,  44:  6683 ; and references therein
• 22 Galopin CC. Tetrahedron Lett.  2001,  42:  5589 ; and references therein
• 23 Shi J.-G. Shi Y.-P. Jia Z.-J. Phytochemistry  1997,  45:  343 
• 24 Le Bideau F. Gilloir F. Nillson Y. Aubert C. Malacria M. Tetrahedron  1996,  52:  7487 
• 27 This compound was synthezised according to literature procedure, see: Velcicky J. Lex J. Schmalz H.-G. Org. Lett.  2002,  4:  565 ; and references cited therein
• 28 Mainetti E. Fensterbank L. Malacria M. Synlett  2002,  923 
• 29 Mash EA. Nelson KA. Tetrahedron  1987,  43:  679 ; and references cited therein
• 30 Cruciani G. Margaretha P. Helv. Chim. Acta  1990,  73:  890 
• 31 Pol AV. Naik VG. Sonawane HR. Indian J. Chem., Sect. B: Org. Chem. Incl. Med. Chem.  1980,  19:  603 

17

This is reminiscent of a result by Toste with a Z-precursor, see ref. 11c.

25

(Z)-Cinnamyl bromide was synthesized in three steps, in 59% overall yield, starting from commercially available phenylacetylene: (1) C-hydroxymethylation [n-BuLi, (CH₂O)_n; 70%]; (2) hydrogenolysis (H₂, Pd, CaCO₃; 94%); (3) bromination (PBr₃, pyridine, 90%).

26

1-Bromomethylcyclohex-1-ene was synthesized in 2 steps (74% overall yield) starting from commercially available cyclohex-1-ene-1-carboxaldehyde through: (1) reduction (NaBH₄, no purification); (2) bromination (PBr₃, pyridine).