Aminomethylation dichloromethane

Another GC/MS method that was validated as a food tolerance method involved the determination of glyphosate and (aminomethyl)phosphonic acid (AMPA) in crops. In this method, glyphosate and AMPA residues are extracted from crop commodities (corn grain) with water. The extracts are then partitioned with dichloromethane,... 

A dry 50 mL Schlenk reaction tube was flushed with nitrogen and charged with a mixture of 7 (527mg, l.Ommol), 1,3-dicyclohexylcarbodiimide (1.04g, 5mmol), pentafluorophenol (920 mg, 5 mmol), 4-(dimethylamino)pyridine as the catalyst and the aminomethylated polystyrene (930 mg, 1.07 mmol g ) in dry dichloromethane (20 mL). The mixture was stirred at room temperature for 24h under a N2 atmosphere. The polymer was filtrated, rinsed sequentially with CH2CI2 and acetone and dried at 50 °C in vacuo to yield the polymer-bound ligand 8 as pale yellow beads. 

Aminomethylated polystyrene (DVB I %, 1.07 mmol Trifluoroacetic acid / dichloromethane (I/I, v/v), 10mL 3-Bromopropionic acid (97 %) (158 mg, I mmol) Cesium carbonate (99.9%) (652 mg, 2 mmol) Triethylamine Benzene Acetone... 

A-Methylimidazole (22.5 /il) was added to a mixture of Fmoc-glycinol (20.0 mg, 0.07 mmol), Fmoc-glycine (27.3 mg, 1.3 equiv.), and polystyryl-sulfonyl chloride resin (61.6 mg, 1.3 equiv., 1.49 mmol/g) in dichloro-methane (1 ml). After 2 h, aminomethylated PS-resin (138 mg, 2 equiv.) was added and the suspension shaken for 30 min. After filtration through a fritted filter, the resin was rinsed thoroughly with dichloromethane, and the combined solvents were concentrated to 3 ml. Amberlyte 15 (176 mg) was added and the suspension was shaken again for 30 min and filtered as described above. After evaporation of the solvent, the pure product was obtained as a colorless foam 93 % yield. 

After washing and drying, part of the resulting resin-bound 2-fluoroar-ylsulfone (1.0 g, approx. 0.74 mmol) was treated twice with a solution of 4-(aminomethyl)pyridine (1.0 ml, 10 mmol) in NMP (20 ml) at room temperature for 2 h. After washing and drying, part of the resulting resin-bound nitroaniline (0.5 g, approx. 0.35 mmol) was treated twice with a solution of piperidine (4.0 ml, 40 mmol) in NMP (20 ml) at 100° for 3 h. After extensive washing with dichloromethane and methanol, part of this... 

Aminomethyl-[l,3]dioxolan-2-yloxy)-N,N-dioctadecyl-butyramide (9) (800 mg, 1.13 mmol, 1 eq), triethylamine (390pi, 2.8 mmol, 2.5 eq), and the acid 15 (800 mg, 1.24 mmol, 1.1 eq) were dissolved in dichloromethane (10 ml). BOP (600 mg, 1.36 mmol, 1.1 eq) was added and the mixture was stirred 2 h at ambient temperature. The reaction medium was concentrated, taken up in ethyl acetate (150 ml), and washed with NaHCOjSat (3x40 ml), NaClsat (40 ml). It was dried over magnesium sulfate, filtrated and evaporated. Column chromatography on silica (EtOAc) gave 1.1 g of a white powder (73%) (see Note 8). 

HMPB resin, an aminomethyl polystyrene resin acylated with 4-hydroxymethyl-3-methoxyphenoxybutyric acid cleavable by extremely mild acidolysis similar to SASRIN (super acid-sensitive resin). Detachment of the final product, even in form of the frilly protected peptides, is achieved with dilute acid (1% TFA/dichloromethane) to yield peptide... 

Figure 9.9 Synthesis of 2-[2-(2,6-dimetho3q heno3g )ethyI]aminomethyl-l,4-benzodioxane including the information given in the paper to elucidate greenness of the s)mthetie path. THF tetrahydrofuran DMSO dimethyl sulfoxide DCM dichloromethane.

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