The reaction of 2,3-dimethylbutene-2 (IV) gives 2,3-dimethyl-3-hydroperoxybutene-1 (V), 6370, b.p. 54' (9 mm.), n Z 4 . 6~ 1.4408; the infrared and n.m.r. spectra are identical with those of the product of the photosensitized autoxidation (formed in 54y0 yield; lit." : 82%, b.p. 55' (12 mm.), n 2 0~ 1.4428).
OH 'C=CTetraphenylcyclopentadienone (VI) gives cis-dibenzoylstilbene (VII, 50%, infrared spectrum identical with that reportedI6). The photosensitized autoxidation gave VI1 in 65% yield.The peroxide VI11 is presumably intermediate.
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CHa
CsHs CsHs
CsHs CsHs CsHsCsHs CsHs
CsHs
VI1
VI11VI Cyclohexadiene-1,3 (IX) gives 5,6-dioxabicyclo-[2.2.2]octene-2 ("norascaridol," X, 20%), with infrared and n.m.r. spectra identical with those of a sample prepared by the photosensitized autoxidation (35% yield; lit." 21y0).
0
IX XPreliminary indications are that rubrene and other aromatic hydrocarbons also form peroxides analogous to those formed photochemically.18Procedve.--.To a solution of 5.05 g. (60 mmoles) of 2,3-dimethylbutene-2 (IV) in 300 ml. of methanol was added 19.2 ml. of 30Y0 H202 [I80 mmoles). The solution was stirred a t IO', and 145.5 ml. of 1.03 M NaOCl solution (150 niequiv.) was added in the course of 90 min. The solution was diluted with water and extracted with ether. Ether was distilled from the dried extracts through a column to prevent loss of the volatile product. The residue was Sample (14) G 0 Srhenck and K . Schulte-Elte, Ann., 618, 185 (1958).(1.5) I) I< Rerger and R . K Summerhell, J . Org. C h c m . , 24, 1881 (1959). ' I R ) C F Wilcor, J r , and M P . Stevens, J Am. Chcm. Soc., 84, 1258 ' I!IR?), C. 0 Schenck, i: Eiiklrochcm , 56, 855 (3952) (17) G 0 Scbenck and W Willmund, reported by R . Criegeein HoubenWeyi, "Methoden der Organischen Chemie," Vol. V I I I . 4th Ed., E Muller, b::l , G e o r g Thieme \'erIag Stuttgart, 1952. p 16. The yields referred to above are of distilled but uru-ecrystallized material. '18i Cnrey has recently found that externally generated singiet 0 3 is capable of oxidizing aromatic hydrocarbons: E. J . Corey and W . C . 'Taylor, J . A m . C h n . COC , 86, 3881 (1964).distilled, giving 4.39 g. (37.8 mmoles, 63%) of V, with the physical constants described above.The new reaction parallels the photosensitized autoxidations in every case so far studied; it appears to be a general and practical synthetic method for oxidization of olefins which give high quantum yields in the photosensitized autoxidation (for example, s-& dienes, furans, and tri-and tetrasubstituted olefins). The products (when they are peroxides) are, of course, readily reduced to the corresponding alcohols. Where the parallel photosensitized autoxidation goes in low quantum yield, it is likely that the peroxide-hypochlorite reaction will be less useful, because of the large quantities of reagents which would be required; this suggestion is supported by preliminary studies. The quantities of oxidant are best adjusted so that nearly 1 mole of oxygen is actually taken up; the oxygen which evolves from...
