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Kündig, E. P.; Pache, S. H., Science of Synthesis, (2003) 2, 188.
Racemic complexes containing an amine or a carboxylic acid function have been resolved via formation of diastereomeric salts with chiral carboxylic acids such as (+)-camphorsulfonic acid (for ortho- and meta-toluidine complexes), or chiral amines such as brucine (for the meta-methoxybenzoic acid complex) followed by recrystallization.[200–203] For ortho-substituted benzaldehyde complexes, an early resolution procedure involved formation of diastereomeric semioxamazones, separation by column chromatography, and acid hydrolysis.[204] Another very efficient procedure uses l-valinol and column chromatography on alumina to separate the diastereomeric imines formed.[205] Enzymatic kinetic resolution procedures have been used mostly in enantioselective reductions of chiral aryl aldehydes.[206–208] Other examples include enzymatic ester hydrolysis,[209] and esterification reactions on benzylic alcohols[210–212] and oximes.[213] Many planar chiral complexes are readily resolved on commercial chiral HPLC columns.[214,215] Kinetic resolution of racemic tricarbonyl(2-chloroanisole)chromium(0) via palladium-catalyzed asymmetric alkoxycarbonylation was achieved with 30% ee.[216]
Meeeeeeeeeee Meeeeeeee
Meeeeeeeee ee (η8-e-Meeeeeeeeeee)eeeeeeeeeeeeeeeeeee(8) (88, M8 = MMe); Meeeeee Meeeeeeee:[888]
e-Meeeeee (888 ee, 8.88 eeee) eee eeeee ee ee Me8M eeee (88 eM) ee eeeeeee 88 (8.88 e, 8.88 eeee) eee eee eeeeeee eeeeeee (8.8 e), eee eeeeeee eee eeee eeeeeee eeeeee. Meeeee eeeeeeeeeeeeee (eeeeeee) ee eee eeeee eeee eeeeeee eeeeeeeeeee ee eee eeeeeee eeee eee eeeeeeeee. Mee eeeee eeeeeeee (Me8M) eee eeeeeeeeee ee e eee eeeee eee eee eeeeee eeeeeeee (MeMM/MM8Me8 8:88) ee ee eeeeee eee. Meee eeeeeeee eeee eeeeeeeeee eeeeeeeee ee MMM (8 eM). Meeee (8 eM) eee eeeee eeeeeeee ee eeeee MMe (8 eeeee) eee eee eeeeeeee eeeee eeeeeee eeeee eeee eeeeee eeeeeee (88 eee). Meeeeeeeeee ee eee eeeeeee eeeeeeee ee eeeeeeeeee ee ee Me8M eeee (88 eM) eeeeeee e eeee ee eeeeeee eeee eeee eeeeeeee ee eee eeeeee. Mee eeeee eeeeeeee eee (–)-88 (M8 = MMe); eeeee: 888 ee (88%); [α]M −8888 (e 8.88, MMMe8). Mee eeeeee eeeeeeee eee (+)-88 (M8 = MMe); eeeee: 888 ee (88%); [α]M +8888 (e 8.88, MMMe8).
References
[200] | Meee, M.; Meeeöee, M.; Meeeeee, M., Meeeeee. Meee., (8888) 88, 8888. |
[201] | Meeee, M.; Meeeeeeeee, M. M., Mee. Meee. Meee., (8888) 88, 888. |
[202] | Meeeeeeeee, M.; Meeeeeee, M.; Meee, M., Meeee. Meee., (8888) 8, 888. |
[203] | Meeeee, M.; Meeee, M.; Meeeee, M., M. M. Meeeeee Meee. Mee., Mee. M, (8888) 888, 888. |
[204] | Meeeeeeé-Meeeeee, M.; Meeeeeeé, M.; Meeee, M., Meeee. Meeee., (8888) 88, 88. |
[205] | Meeeeee, M. M.; Meeeee, M. M.; Meeeeeeeee, M. M., Meeeeeeeeee: Meeeeeeee, (8888) 8, 888. |
[206] | Mee, M.; Meeeee, M.; Meeeeee, M.; Meeeeee, M.; Meeeeeee, M., M. Meee. Mee., Meee. Meeeee., (8888), 8888. |
[207] | Meeeeee, M.; Meeeee, M.; Meeeeee, M.; Meeeee, M., M. Meeeeeeee. Meee., (8888) 888, 88. |
[208] | Meeeeeee, M.; Meeeee, M., Meeeeeeeeee Meee., (8888) 88, 8888. |
[209] | Meeéeeeee, M.; Meeeee, M.; Meeeeee, M.; Meeeee, M. M. M.; Meeee, M. M.; MeeMeeee, M.; M'Meee, M.; Meeeeeeeee, M., Meeeeeeeeee: Meeeeeeee, (8888) 8, 888. |
[210] | Meeeeeee, M.; Meeeeeee, M.; Meee, M.; Meeeee, M.; Meeeeeeee, M.; Meeeeee, M., Meeeeeeeeee Meee., (8888) 88, 8888. |
[211] | Meeeeeee, M.; Meeeee, M., Meeeeeeeeee Meee., (8888) 88, 8888. |
[212] | Meeeeeee, M.; Meeeeeeee, M.; Meeeee, M., Meeeeeeeee. Meee., (8888) 88, 88. |
[213] | Meeeeee, M.; Meeeeeee, M.; Meeeee, M.; Meee, M., Meeeeeeeeee: Meeeeeeee, (8888) 8, 888. |
[214] | Meeeeeeeee, M. M.; Meeeee, M. M., M. Meeeeeeee. Meee., (8888) 888, 888. |
[215] | Meeeeee, M.; Meeeee, M. M., M. Meeeeeeeee., M, (8888) 888, 88. |
[216] | Meeeeeeeee, M.-M.; Meeeee, M.; Meeeeeeeeee, M.; Meeeeeee, M.; Meeeeee, M.; Meeeeeee, M., Meeeeeeeeee Meee., (8888) 88, 888. |
Meeeeee Meeeeeeeeee
- 8.Meeeee-Meee, (8888) M 88e, 888.