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Organic syntheses vol 58 - Sheppard W.A.

Sheppard W.A., Buchi G.H. Organic syntheses vol 58 - Wiley, 1978. - 123 p.
Download (direct link): organicsynthesesvol581978.pdf
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20. B. S. Pitzele, J. S. Baran, and D. H. Steinman, J. Org. Chem., 40, 269 (1975).
21. L. S. Trzupek, T. L. Newirth, E. G. Kelley, N. E. Sbarbati, and G. M. Whitesides, J. Amer. Chem. Soc., 95, 8118 (1973).
22. M. W. Rathke and R. Kow, J. Amer. Chem. Soc., 94, 6854 (1972); R. Kow and M. W. Rathke, J. Amer. Chem. Soc., 95, 2715 (1973); D. S. Mattcson and R. J. Moody, J. Amer. Chem. Soc., 99, 3196 (1977).
23. G. E. Gream, L. R. Smith, and J. Meinwald, J. Org. Chem., 39, 3461 (1974).
24. M. R. Wasielewski, Tetrahedron Lett., 1373 (1977).
Appendix
Chemical Abstracts Nomenclature (Collective Index Number; Registry Numbers)
Lithium 2,2,6,6-tetramethylpiperidide: Piperidine, 2,2,6,6-tetra-methyl-, lithium salt (8,9); (38227-87-1)
l-Ethoxy-2-p-tolylcyclopropane: Ether, ethyl 2-p-tolylcyclopropyl
(8); Benzene, l-(2-ethoxycyclopropyl)-4-methyl- (9); cis-(40237-67-0); (rans-(40489-59-6)
p-Xylene, a-chloro- (8); Benzene, l-(chloromethyl)-4-methyl- (9); (Ů4-82-5)
Ether, ethyl vinyl (8); Ethene, ethoxy- (9): (109-92-2)
CATALYTIC OSMIUM TETROXIDE OXIDATION OF OLEFINS 43
Piperidine, 2,2,6,6-tetramethyl- (8,9); (768-66-1)
Citric acid (8); 1,2,3-Propanetricarboxylic acid, 2-hydroxy- (9); (77-92-9)
Hydrazine (8,9); (302-01-2)
4-Piperidone, 2,2,6,6-tetramethyl- (8); 4-Piperidinone, 2,2,6,6-tetramethyl- (9); (826-36-8)
Methyl bromide: Methane, bromo- (8,9); (74-83-9)
1,10-Phenanthroline (8,9); (66-71-7)
Lithium, butyl- (8,9); (109-72-8)
l-Methoxy-2-phenylcyclopropane: Ether, methyl 2-phenyl-cyclopropyl, trans- (8); Benzene, (2-methoxycyclopropyl)-, trans-
(9); (26269-57-8)
Ether, dichloromethyl methyl (8); Methane, dichloromethoxy- (9); (4885-02-3)
Styrene (8); Benzene, ethenyl- (9); (100-42-5)
Methyl thiobenzoate: Benzoic acid, thio-, S-methyl ester (8); Ben-zenecarbothioic acid, S-methyl ester (9); (5925-68-8)
Benzamide, N,N-dimethyl- (8,9); (611-74-5)
Propiolic acid (8); 2-Propynoic acid (9); (471-25-0) Tetracyclo[4.2.0.02,4.035]oct-7-ene (8,9); (35434-65-2)
Lithium diisopropylamide: Diisopropylamine, lithium salt (8); 2-Propanamine, N-(l-methylethyl)-, lithium salt (9); (4111-54-0) Lithium, methyl- (8,9); (917-54-4)
CATALYTIC OSMIUM TETROXIDE OXIDATION OF OLEFINS: cis -1,2-CY CLOHEX ANEDIOL
CH
H3C o0
30% aqueous H2O2
75░, 22.5 hours
1
44
ORGANIC SYNTHESESŚVOL. 58
2
Submitted by V. VanRheenen, D. Y. Cha, and W. M. Hartley1 Cheeked by N. Meyer, W. Wykypiel, and D. Seebach
1. Procedure
Caution! Care should be taken in handling osmium tetroxide. The vapor is toxic, causing damage to eyes, respiratory tract, and skin.
A. N-Methylmorpholine N-oxide (1) (Note 1). A 100-ml., threenecked, round-bottomed flask is equipped with a reflux condenser, a magnetic stirring bar, and a dropping funnel. The flask is flushed with nitrogen or argon and charged with 35.1ml. (32.3 g.,
0.32 mole) of i\ methylmorpholine (Note 2). The flask is immersed in an oil bath maintained at 75░, and 29.1 ml. (32.4 g., 0.286 mole) of 30% aqueous hydrogen peroxide is added dropwise over a period of 2.5 hours (Note 3). The mixture is then stirred for 20 hours at 75░. At this time a negative peroxide test (KI paper) is obtained (Note 4). The reaction mixture is cooled to 50░, and a slurry of 50 ml. of methanol, 0.5 g. of charcoal, and 0.5 g. of Celite (Note 5) is added. After being stirred for 1 hour, the mixture is filtered and the filter cake washed three times with 15-ml. portions of methanol. The filtrate and combined washings are concentrated in a rotary evaporator (water aspirator vacuum), with the bath temperature finally reaching 95░, where it is held for 10 minutes. The flask is fitted with a reflux condenser, and the residual viscous
oil is dissolved in 25 ml. of acetone at 60░. On cooling to 40░ (with seeding, if crystals of the N-oxide are available) the product spontaneously crystallizes. The slurry is stored at room temperature overnight, cooled in an ice bath, and filtered. The crystals are washed three times with 15-ml. portions of 0░ acetone and dried overnight at 40░ (0.01 mm.) The yield of colorless crystalline monohydrate 1 is 32.4-34.3 g. (83.8-88.7%), m.p. 75-76░ (Notes 6 and 7).
CATALYTIC OSMIUM TETROXIDE OXIDATION OF OLEFINS
45
B. cis-1,2-Cyclohexanediol (2). A 250-ml., three-necked, round-bottomed flask, with a magnetic stirrer and a nitrogen inlet, is charged with 14.81 g. of monohydrate 1 (0.106 mole), 40 ml. of water, and 20 ml. of acetone. To this solution is added ca. 70mg. of osmium tetroxide (0.27 mmole) (Note 8) and 10.1ml. (8.2 g.,
0.1 mole) of cyclohexene (Note 9). This two-phase solution is vigorously stirred under nitrogen at room temperature. The reaction is slightly exothermic and is maintained at room temperature with a water bath. During the overnight stirring period, the reaction mixture becomes homogeneous and light brown in color. After 18 hours, thin-layer chromatography (Note 10) shows the reaction to be complete. Sodium hydrosulfite (0.5 g.) (Note 11) and 5 g. of Mag-nesol (Note 12) slurried in 20 ml. of water are added, the slurry is stirred for 10 minutes, and the mixture is filtered through a pad of 5 g. of Celite on a 150-ml. sintered-glass funnel. The Celite cake is washed with three 15-ml. portions of acetone. The filtrate, combined with acetone wash, is neutralized to pH 7 with 6.4 ml. of 12╦├ sulfuric acid. The acetone is evaporated under vacuum using a rotary evaporator. The pH of the resulting aqueous solution is adjusted to pH 2 with 2.3 ml. of 12JV sulfuric acid, and the cis-diol
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