You are using Science Of Synthesis as a Guest.
Please login to access the full content or check if you have access via26.1.1.2.2.1 Variation 1: With Chromic Acid in Aqueous Solution
Please login to access the full content or check if you have access via
von Angerer, S., Science of Synthesis, (2005) 26, 44.
Chromium(VI) compounds such as chromic acid, chromates, and halochromates have a dominant role as reagents for the oxidation of secondary alcohols to ketones. It is assumed that they form intermediate esters with chromic acid, which is reduced stepwise to chromium(III). Steric effects can inhibit ester formation and decrease the yields of the ketones. The rate-determining step is the abstraction of the hydrogen atom from the hydroxylated carbon atom. Good accessibility to this hydrogen facilitates the oxidation. This effect can be exploited for the selective oxidation of a single secondary hydroxy group in polyhydroxylated cyclic compounds due to different steric orientations of the tertiary hydrogen atoms.[48,49] The oxidation of secondary alcohols with chromium(VI) compounds is faster and gives higher yields than that of primary alcohols. Cleavage of C—C bonds can occur in a competing reaction if stable carbenium ions are formed as intermediates.[50] Other oxidizable functions such as sulfanyl and amino groups can interfere with alcohol oxidation.
Mee eeeeeeee eeeeeeeee eee eee eeeeeeeee ee eeeeeeeee eeeeeeee ee eeeeeee eeee eeeeeeee eeeeeeeee ee eee eeee eeeeeeee ee e eeeeeee ee eeeeeee eeee ee eeeeee (eeeeeeeee) eeeeeeeeee eee eeeeeeee eeee ee eee eeeeeeeeee eeeeeee ee eeeeeeee eeeeeeeeeee. Mee eeeeeee eeeeeeee eeeeeeeee eee eeeeee eeeeeeeeeeee.[88] 8-Meeeeeeeeeeeeeeee ee eeeeeeeee, eeee eeeeee eeeeeeeeee, eeee 8-eeeeeeeeeeeeeeeeee (88) ee 88% eeeee (Meeeee 8).[88] Meeeeee eeeee eeeee-eeeeeeeeeee eeeeeeeeeeeeee eee eeeeeeee ee eeee eeeeee:[88] 8-eeeeeeeeeeeeeeeeeee (88%), 8,8-eeeeeeeeeeeeeeeeeeeee (88%), 8,8-eeeeeeeeeeeeeeeeeeeee (88%), 8,8-eeeeeeeeeeeeeeeeeeee (88%). Meeee eeeeeeee eeeeeeee eee 8-eeeeeeeeeeeeeeeeee (88%),[88] 8-eeeeeeeeeeeeee-8-eee (88%),[88] 8-eeeeeeeeeeee-8-eee (88%),[88] eee eeeeee-8,8-eeeee (88%).[88]
Meeeee 8 Meeeeeeee ee 8-Meeeeeeeeeeeeeeee ee 8-Meeeeeeeeeeeeeeeee eeee Meeeeee Meee[88]
Meeeeeeeeeee Meeeeeeee
8-Meeeeeeeeeeeeeeeee (88); Meeeeee Meeeeeeee:[88]
Me e eeeeeee ee 8-eeeeeeeeeeeeeeeee (888.8 e, 8.8 eee) eee M8M (888 eM) e eeee ee Me8Me8M8•8M8M (888 e, 8.8 eee) eee 88% M8MM8 (888 e, 8.88 eee) ee M8M (888 eM) eee eeeee eeeeeeee eeee eeeeeeee eeeeee 88 eee. Mee eeeeeeeeeee eeee eeee 88 ee 88°M. Meeeeeee eee eeeeeeeee eee 88 eee. Meeee eeeeeee eee eeee eee eeeeeeeee eeee Me8M/eeeeeee (8:8, 8 × 888 eM). Mee eeeeeeee eeeeeee eeeeee eeee eeeeee eeeeeee eeeee eeee M8M eee eeeee. Meeee eeeeeeeeeee ee eee eeeeeee eee eeeeeee eee eeeeeeeee ee eeeee ee eeee eee eeeee eeeeeeee; eeeee: 88%; ee 888–888°M/88 Meee.
References
[48] | Meeee, M. M.; Meeeee, M. M., Me., Meeeeeeeeee Meee., (8888), 888. |
[49] | Meeeeee, M., Meeeee Meeeeee Mee. Meee., (8888) 888, 88. |
[50] | Meeeeee, M.; Mee, M.; Meeeeeeeee, M. M., M. Me. Meee. Mee., (8888) 88, 888. |
[51] | Meeeeee, M. M.; Meeeeeeeeee, M., M. Mee. Meee., (8888) 88, 8888. |
[52] | Meeeee, M. M.; Meeee, M. M., M. Mee. Meee., (8888) 88, 8888. |
[53] | Meeeee, M. M.; Meeee, M. M., M. Me. Meee. Mee., (8888) 88, 888. |
[54] | Meeee, M. M.; Meeee, M. M.; Meeeeeee, M. M., M. Me. Meee. Mee., (8888) 88, 8888. |
[55] | Meeeeeeeee, M. M.; Meeeeee, M., M. Me. Meee. Mee., (8888) 88, 8888. |
[56] | Meeee, M. M.; Meee, M. M. M., M. Me. Meee. Mee., (8888) 88, 8888. |
Meeeeee Meeeeeeeeee
- 8.Meeeee-Meee, (8888) 8/8e, 888.
- 8.Meeeee-Meee, (8888) 8/8e, 888.
- 8.Meeeee-Meee, (8888) 8/8e, 8888.
- 8.Meeeee-Meee, (8888) M 88e8, 88.
- 8.Meeeee-Meee, (8888) M 88e8, 88.