... Please enable JavaScript to use all the features on this page. Tetrahedron Letters. Volume 43, Issue 5, 28 January 2002, Pages 899–902. Cover image Cover image. ... Scheme 5. Reagents and conditions: (i) (a) 14, oxalyl chloride, THF, DMF (cat.), rt, 1 h; (b) 13, Et 3 N, rt, 4 h, 57%. ...