An Investigation into Solid-Phase Radical Chemistry - Synthesis of Furan Rings

Synlett

Volumn 1997, Issue 1, 1997, Pages 61-62

  Routledge, Anne ^a   Abell, Chris ^a   Balasubramanian, Shankar ^a  

^a UNIVERSITY OF CAMBRIDGE   (United Kingdom)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0002464476     PISSN: 09365214     EISSN: None     Source Type: Journal    
DOI: 10.1055/s-1997-704     Document Type: Article

References (15)

1. Giese, B. Radicals in Organic Synthesis; Formation of Carbon-Carbon Bonds; Pergamon Press: Oxford, 1986.
2. Curran, D.P. Synthesis, 1988, 417-439 and 489-513.
3. Bowman, W.R.; Heaney, H.; Jordan, B.M. Tetrahedron Lett., 1988, 29, 6657-6660.
4. Synthesised from chloromethyl polystyrene resin (Polymer Laboratories, 3.5 mmol/g). Darling, G.D.; Frechet, J.M.J. J. Org. Chem., 1986, 51, 2270-2279.
5. Yields determined by either gravimetric or microanalytical data.
6. t-BuOH was present to supress the formation of the β-elimination product.
7. Determined by t.l.c. analysis of cleavage mixture indicating no uncyclised material present.
8. 3SnH, t-BuOH (3:1, 400 μl), a solution of AIBN in toluene (0.016 M, 50 μl, 3% mol eq) was added and the mixture heated at 100°C under argon for 5 h. A further portion of AIBN (50 μl, 3% mol eq) was added and heating was continued for 15 h. The resin was washed with dioxane (3x5 ml), DMF (3x5 ml), toluene (3x5 ml) and dichloromethane (3x5 ml) then dried under vacuum for 24 h.
9. Ueno, Y.; Chino, K.; Okawara, M. Tetrahedron Lett., 1982, 23, 2575-2576. Other workers have contradicted these results stating that yield of cyclised products are not influenced by the concentration of tributyltin hydride. Shankaran, K.; Sloan, C.P.; Snieckus, V. Tetrahedron Lett., 1985, 26, 6001-6004.
10. Ueno, Y.; Chino, K.; Okawara, M. Tetrahedron Lett., 1982, 23, 2575-2576. Other workers have contradicted these results stating that yield of cyclised products are not influenced by the concentration of tributyltin hydride. Shankaran, K.; Sloan, C.P.; Snieckus, V. Tetrahedron Lett., 1985, 26, 6001-6004.
11. Detection by g.l.c.
12. Beckwith, A.L.J.; Schiesser, C.H. Tetrahedron, 1985, 41, 3925-3941.
13. Radical cyclisations of iodoacetylenic esters with moderate amounts of tributyltin hydride gave unidentified organotin containing species as byproducts. Haaima, G.; Lynch, M.-J.; Routledge, A.; Weavers, R.T. Tetrahedron, 1993, 49, 4229-4252.
14. Tortolani, D.R.; Biller, S.A. Tetrahedron Lett, 1996, 37, 5687-5690.
15. 3SnH, toluene (1:3, 400 μl), a solution of AIBN in toluene (0.016 M, 60 μl, 5% mol eq) was added and the mixture heated at 80°C under argon for 2 h. The resin was washed with toluene (3x5 ml), DMF (3x5 ml), toluene (3x5 ml) and dichloromethane (3x5 ml) then dried under vacuum for 24 h. N.B prolonged reaction times and elevated temperatures result in substantial cleavage of the cyclised product into solution.