Atom-transfer cyclization with CuSO4/KBH4 : a formal “activators generated by electron transfer” process also applicable to atom-transfer polymerization
Clark, Andrew J., Collis, Alana, Fox, David J., Halliwell, Lauren L., James, Natalie, O’Reilly, Rachel K., Parekh, Hemal, Ross, Andrew, Sellars, Andrew B., Willcock, Helen and Wilson, P. (Paul). (2012) Atom-transfer cyclization with CuSO4/KBH4 : a formal “activators generated by electron transfer” process also applicable to atom-transfer polymerization. Journal of Organic Chemistry, Vol.77 (No.16). pp. 6778-6788. ISSN 0022-3263Full text not available from this repository.
Official URL: http://dx.doi.org/10.1021/jo301429a
The 4-exo and 5-exo-trig atom-transfer cyclizations of 1, 8a–e, 9, 12, and 13 can be mediated with as little as 0.05 mol % of Cu(TPMA)SO4·5H2O in the presence of 2.5 mol % of borohydride salts in 10 min at room temperature in air. This formal “activators generated by electron transfer” (AGET) procedure utilizes a cheap and oxidatively stable copper source (CuSO4·5H2O) and can be carried out in environmentally benign solvents (EtOH). It is possible to alter the product distribution in the 5-endo radical–polar crossover reactions of 10a,b and 11 by tailoring the amount of borohydride. Cyclization onto alkynes 14 and 15 is also possible in only 20 min. Controlled radical polymerization of styrene, with increased rates over conventional atom-transfer radical polymerization (ATRP), can be carried out in a controlled fashion (Mn, PDI) using either CuBr or CuSO4·5H2O and Bu4NBH4.
|Item Type:||Journal Article|
|Subjects:||Q Science > QD Chemistry|
|Divisions:||Faculty of Science > Chemistry|
|Journal or Publication Title:||Journal of Organic Chemistry|
|Publisher:||American Chemical Society|
|Date:||17 August 2012|
|Page Range:||pp. 6778-6788|
|Access rights to Published version:||Restricted or Subscription Access|
|Funder:||University of Warwick , Engineering and Physical Science Research Council (EPSRC), Advantage West Midlands (AWM) , European Regional Development Fund (EDRF)|
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