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15th March 2012 @ 03:34
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To overcome solubility issues with glycinamide, the salt-break and imine formation will be attempted in aqueous methanolic conditions employing sodium cyanoborohydride as reducing agent.

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Reaction Start Time: 15.00 15/03/12
Glycinamide hydrochloride (66 mg, 0.60 mmol, 1.3 equiv.) was dissolved in water (approx 0.2 mL). 1M NaOH solution (1 mL, 1 mmol, 2.2 equiv.) was added followed by aldehyde PMY 2-5 (100 mg, 0.46 mmol, 1 equiv.). Methanol was added to the slurry until dissolved (approx. 15-20 mL) and the mixture stirred for 1.5 hours. Sodium cyanoborohydride (43 mg, 0.69 mmol, 1.5 equiv) was added as a solution in methanol (2 mL). Drying with MgSO4 was omitted due to potential for the glycinamide to precipitate if water is removed. If no reaction is observed, the reaction will be dried. After 2 hours, no reaction. Stirred at room temperature overnight. No reaction by TLC. MgSO4 added and the reaction heated to reflux. 19/03/12 Reaction is complete by TLC with a single less-polar product spot. Desired product should be considerably more polar than SM. Reaction is a colourless solution with white powder. Reaction cooled and filtered, washed through with further MeOH. The filtrate was concentrated under reduced pressure. The residue was stirred in DCM (50 mL) and washed with 10% NaHCO3 (10 mL), brine then dried (MgSO4) and concentrated under reduced pressure to a brown oil (77 mg). 1H NMR shows only one product. Unknown, only additional Methyl singlet. Not consistent with desired product.

TLC (10% MeOH/DCM) visualised with UV and vanillin:
TLC before workup
TLC 3 hours, reflux
Initial TLC


NMR:
1H NMR crude


Reference:
doi:10.1002/0471264180.or059.01
http://www.orgsyn.org/orgsyn/orgsyn/prepContent.asp?prep=cv6p0499

Risk and Hazard Assessment:
Risk Assessment diagram
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Scheme
Risk Assessment
Risk Assessment diagram
Scheme
TLC 3 hours, reflux
Initial TLC
TLC before workup
1H NMR crude