Hmmm
Thats confusing. A difference in catalyst could bee the problem. In the article they attempted without water and the yeilds were low.
Since addition of water disfavors imine formation they hypothesize that the reaction proceeds thru direct reduction of the hemiamino intermediate, instead of thru the imine. Hemiamino has both an alcohol and amine on the same carbon.
Wonder if you may have reduced the benzene ring?
Fully Informed Jury! (http://www.fija.org/)
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"And, I don't know why, but I've always thought that CTH reductions only could take place in anhydrous conditions, or just the water formed in rxn."
You may bee thinking of Imine formation which is inibited/reversed by the presence of water. The authors also were puzzled that water increased yeilds. This lead them to propose an alternate reduction mechanism that bypasses the imine by direct reduction of the hemiaminal intermediate I mentioned above.
I'll try to get you the details.
Foxy
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CAL-B-catalyzed resolution of some pharmacologically interesting beta–substituted isopropylamines
Javier González-Sabín, Vicente Gotor, and Francisca Rebolledo
Tetrahedron: Asymmetry 13(12), 1315-1320 (2002)
DOI:10.1016/S0957-4166(02)00336-1 (http://dx.doi.org/10.1016/S0957%2D4166%2802%2900336%2D1)
Synthesis of racemic amines. General procedure.
A slight modification of a reported method [17] was adopted for the synthesis of these compounds. To a solution of the appropriate phenylacetone (20 mmol) in deoxygenated methanol (52 mL), water (6 mL) and ammonium formate (0.21 mol) were added. After complete dissolution, 10% Pd/C (0.80 g, 0.75 mmol) was added and the mixture stirred at room temperature until disappearance of the ketone (TLC control, ethyl acetate: methanol, 4:1). Then, the catalyst was filtered on Celite®, washed with methanol and the solvents were evaporated. The residue was treated with conc. aq. HCl (4 mL) and water (30 mL) and extracted with diethyl ether (2×20 mL). Aqueous phase was treated with solid NaOH until pH basic, and extracted with diethyl ether (3×25 mL). Evaporation of the organic phase yielded the corresponding amine. A second fraction of amine was obtained by continuous extraction of the basic aqueous phase (dichloromethane, 14 h). Crude amine was purified by distillation under reduced pressure. Distillation temperatures (0.5 Torr) and yields of the amine are as follows:
Amphetamine, 1 (45°C, 80%)
o-MeO-Amphetamine, 2 (68°C, 75%)
m-MeO-Amphetamine, 3 (72°C, 72%)
p-MeO-Amphetamine, 4 (60°C, 79%)
References
17.
Tetrahedron Lett. 42, 4257–4259 (2001) (https://www.thevespiary.org/rhodium/Rhodium/pdf/redamin-pdc-af.pdf)
(https://www.thevespiary.org/rhodium/Rhodium/pdf/redamin-pdc-af.pdf)
Post 265571 (https://www.thevespiary.org/talk/index.php?topic=8908.msg26557100#msg26557100)
(foxy2: "Reductive Amination for primary amines", Methods Discourse)