124688-06-8Relevant articles and documents
The role of oxygen acidity on the side-chain fragmentation of ring methoxylated benzocycloalkenol radical cations
Bellanova, Monica,Bietti, Massimo,Salamone, Michela
, p. 6401 - 6404 (2003)
The reactivity of 2,2-dimethyl-5-methoxyindan-1-ol (1) and 2,2-dimethyl-6-methoxytetral-1-ol (2) radical cations has been studied both in acidic and basic solution. At pH≤4 both 1.+ and 2.+ undergo Cα-H deprotonation as the exclusive reaction with k=4.6×104 and 3.2×104 s-1, respectively. In basic solution 1.+ and 2.+ behave as oxygen acids undergoing -OH-induced α-OH deprotonation in a diffusion controlled process (k-OH≈1010 M-1 s-1). An intermediate alkoxyl radical is formed which undergoes a 1,2-hydrogen atom shift in competition with C-C β-scission (with 1.+) or as the exclusive pathway (with 2.+). A behavior which is interpreted in terms of the greater ease of ring-opening of a five membered ring as compared to a six-membered one.