D. Rosenthal, C. F. Lefler andM. E. Wall, Tetrahedron Lett. 3203 (1965); Tetrahedron23, in press (1967).
R. Criegee, inNewer Methods of Preparative Organic Chemistry (Academic Press, New York 1963), vol. II, p. 36.
The isolation of lead hydroxy methoxy diacetate from methanol and lead tetraacetate has been reported byR. Criegee, L. Kraft andB. Rank, Justus Liebigs Annln Chem.507, 199 (1933).
M. Lj. Mihailović, Z. Maksimović, D. Jeremić, Ž. Čeković, A. Milovanović
, 1395 (1965).CrossRef
K. Heusler andJ. Kalvoda, Angew. Chem., Int. Edn3, 525 (1964);G. Cainelli, B. Kamber, J. Keller, M. Lj. Mihailović, D. Arigoni andO. Jeger, Helv. chim. Acta44, 518 (1961).
This assumption is supported by the fact that when the alcohol I was irradiated at room temperature in benzene solution in the presence of lead tetraacetate, the enol ether II was formed. The reason that very little III was isolated can be explained by the fact that in the photolysis reaction the concentration of both reactants was very low. Since the reaction proceeds both thermally and photolytically, it is implied that alkoxy radicals rather than alkoxy cations are intermediates (J. Kalvoda andK. Heusler, Chemy Ind. 1431, 1963).
G. Cainelli, B. Kamber, J. Keller, M. Lj. Mihailović, D. Arigoni
, Helv. chim. Acta44
, 518 (1961);F. D. Greene, M. L. Savitz, F. D. Osterholtz, H. H. Lau, W. N. Smith
andP. M. Zanet
, J. org. Chem.28
, 55 (1963).CrossRef
K. Heusler, J. Kalvoda, G. Anner
, Helv. chim. Acta46
, 352 (1963).CrossRef
H. Wieland, Ber. dt. chem. Ges.44, 2550 (1911);M. S. Kharasch, A. C. Poshkus, A. Fono andW. Nudenberg, J. org. Chem.16, 1458 (1951).
B. M. Lynch andK. H. Pausacker, Aust. J. Chem.10, 40 (1957);D. R. Augood andG. H. Williams, Chem. Rev.57, 123 (1957)
J. D. Bacha andJ. K. Kochi, J. org. Chem.30, 3272 (1965);C. Walling andA. Padwa, J. Am. chem. Soc.85, 1593 (1963).
Electronic factors are not the sole determinants of the mode of cleavage. In certain strained cyclobutanol systems, the normal direction of cleavage is reversed and primary groups are extruded in preference to secondary groups.M. Amorosa, L. Caglioti, G. Cainelli, H. Immer, J. Keller, H. Wehrli, M. Lj. Mihailović, K. Schaffner, D. Arigoni
, Helv. chim. Acta.45
, 2674 (1962);J. Fried
andJ. W. Brown
, Tetrahedron Lett. 1677 (1966).CrossRef
F. F. Rust, F. H. Seubold andW. E. Vaughan, J. Am. chem. Soc.70, 3258 (1948).
C. D. Cook, R. C. Woodworth
, J. Am. chem. Soc.78
, 4159 (1956).CrossRef
W. H. Starnes, Jr.
andN. P. Neureiter
, J. org. Chem.32
, 333 (1967).CrossRef
E. W. R. Steacie,Atomic and Free Radical Reactions (Reinhold Publishing Corp., New York 1954), Chaps. IV and V.
F. D. Greene, C.-C. Chu, andJ. Walia, J. org. Chem.29, 1285 (1964);P. S. Skell andP. D. Readio, J. Am. chem. Soc.86, 3334 (1964).
Compound II was shown independently to be involved in an alternate ionization to form an allylic carbonium ion with very different solvolysis products. The distinction between the cations derived fromβ
alkoxy allylic alcohols by the protonation of theα
carbon atom and the ion obtained by protonation of the hydroxyl group has been made previously.E. Wenkert
andD. P. Strike
, J. Am. chem. Soc.86
, 2044 (1964).CrossRef
C. Walling, inMolecular Rearrangements (Ed.P. de Mayo; Interscience, New York 1963), p. 418.
M. Lj. Mihailović, Lj. Lorenc, M. Gašić, M. Rogić, A. Melera
, 2345 (1966).CrossRef
M. Akhtar andS. March, J. chem. Soc. c, 937 (1966).
R. Criegee andH. Zogel, Ber. dt. chem. Ges.84, 215 (1951).
R. Criegee andW. Schnorrenberg, Justus Liebigs Annln Chem.560, 141 (1948).