35909-25-2Relevant academic research and scientific papers
THE OBSERVATION OF REMARKABLE EFFECTS OF REMOTELY CONNECTED BUT SPATIALLY PROXIMATE HYDROXY-GROUPS ON THE RATES AND REGIOCHEMISTRY OF THE BRICH REDUCTION OF AROMATIC RINGS AND DOUBLE BONDS
Cotsaris, Evangelo,Paddon-Row, Michael N.
, p. 1487 - 1500 (2007/10/02)
Product and competitive-rate studies of Brich reduction (Li, ButOH, NH3) of a series of alicyclic compounds, (6)-(13), are described.The hydrocarbons (6a)-(8a) and the syn-methoxy derivative (6c) are slowly reduced to give the unconjugated dienes such as (16a).In contrast the syn-alcohols (6b)-(8b) were rapidly reduced to give the monoenes (17), (19), and (22), respectively.Reduction of the syn-alcohol (10b) was also extremely rapid but that of the norbornenols (11a) and (12a) only showed moderate rate enhancements.Each of the above alcohols displays intramolecular OH...? bonding.Brich reductions of (1), (6a), (10a), (11b), and (12b), none of which possess intramolecular OH...? bonds, appear to obey third-order kinetics whereas those of the OH...?-bonded alcohols (6b), (10b), (11a), and (12a) followed a combination of second- and third-order kinetics .The rate and product data for the reduction of the alcohols (6b)-(8b), (10b), (11a), and (12a) are explained in terms of the presence of intramolecular OH...? bonding in these substrates.The observed second-order kinetics are explained in terms of intramolecular protonation of the anion-radical intermediate and is supported by the data for reduction of (6c) and (9).Geometric features which affect the efficacy of intramolecular proton transfer are discussed.Full STO-3G geometry optimisations on the anion radicals of (11a and b) reveal the presence of strong OH...? bonding in the anion-radical of (11a) amounting to some 27 kJ mol-1.
Steric Effects in endo,exo-Tetracyclo3,6.02,7>dodecanes: Influence of 4-Substituents on the Solvolysis of Epimeric 11-Sulfonates
Lenoir, Dieter,Frank, Robert M.
, p. 3336 - 3348 (2007/10/02)
By stereoselective additions of 11-anti-acetoxy-endo,exo-tetracyclo3,6.02,7>dodec-4-ene (12a) compounds 6, 13 - 18 have been prepared.Olefin 19, obtained by Wittig reaction from 17, was hydrogenated yielding methyl compound 9
