121637-55-6Relevant articles and documents
CYCLIZATION OF ACYCLIC ISOPRENOIDS. IV. RING CLOSURE WITH FORMATION OF A C2-OXYGEN BOND
Gavrilyuk, O. A.,Korchagina, D. V.,Osadchii, S. A.,Barkhash, V. A.
, p. 871 - 885 (2007/10/02)
Experimentally substantiated schemes are proposed for the first time for the cyclization of a series of the most important representatives of acyclic isoprenoids (citral, diisopentenylacetone, dehydrolinalool), and the intermediate carbocations were detected by NMR.In all cases the proton adds at the 2,3-double bond, and cyclization takes place by reaction of the C2 cationic center with the oxygen of the carbonyl or hydroxyl group.The cyclization of the structural analog of citral (citronellal) takes place in a different way.In this case the 2,3-double bond acts as internal nucleophile.The great synthetic possibilities of the cyclization of acyclic isoprenoids in superacids in comparison with the conditions of acid catalysis are demonstrated.