von Gast » 26.05. 2005 09:07
Nick hat geschrieben:gibst du das ganze in spuren zu?
das einzige was ich so auf die schnelle gefunden habe, ist eine milde saeurakatalyse.
bin leider (gottseidank) nicht auf der organischen seite der chemie gelandet, deswegen weiss ich nicht was das OZ in PhAcOZ-Cl ist.
PhAcOZ = N-Phenylacetoxybenzyloxycarbonyl
TMS-Cl wird nicht in Spuren zugegeben:
http://www3.interscience.wiley.com/cgi- ... /HTMLSTART
"N-Phenyacetoxybenzyloxycarbonyl-L-aspartic -allyl ester (14): Triethylamine (7.5 mmol) and trimethylsilyl chloride (TMSCl) (1.63 g, 15 mol) were added in one portion to a vigorously stirred suspension of 13 (1.57 g, 7.5 mmol) in CH2Cl2 (25 mL). The mixture was heated at reflux for 1 h, cooled to 0 °C, and diisopropylethylamine (2.2 mL, 13 mmol) and PhAcOZ-Cl (1.5 g, 5 mmol) were added. The reaction mixture was stirred at 0 °C for 30 min and at RT for 2 h. The solvent was removed in vacuo, and the residue was taken up in Et2O (25 mL) and 0.5 M NaHCO3 solution (50 mL). The layers were separated, and the aqueous layer was extracted with Et2O (10 mL). The combined organic layers were washed with H2O (10 mL). The pH of the combined aqueous layers was adjusted to pH 2 with HCl (0.5 M), and the aqueous solution was extracted with ethyl acetate. The combined organic layers were then dried with MgSO4 and concentrated to give the desired product 14 (1.55 g, 70 %)."
[quote="Nick"]gibst du das ganze in spuren zu?
das einzige was ich so auf die schnelle gefunden habe, ist eine milde saeurakatalyse.
bin leider (gottseidank) nicht auf der organischen seite der chemie gelandet, deswegen weiss ich nicht was das OZ in PhAcOZ-Cl ist.[/quote]
PhAcOZ = N-Phenylacetoxybenzyloxycarbonyl
TMS-Cl wird nicht in Spuren zugegeben: http://www3.interscience.wiley.com/cgi-bin/fulltext/93514370/HTMLSTART
"N-Phenyacetoxybenzyloxycarbonyl-L-aspartic -allyl ester (14): Triethylamine (7.5 mmol) and trimethylsilyl chloride (TMSCl) (1.63 g, 15 mol) were added in one portion to a vigorously stirred suspension of 13 (1.57 g, 7.5 mmol) in CH2Cl2 (25 mL). The mixture was heated at reflux for 1 h, cooled to 0 °C, and diisopropylethylamine (2.2 mL, 13 mmol) and PhAcOZ-Cl (1.5 g, 5 mmol) were added. The reaction mixture was stirred at 0 °C for 30 min and at RT for 2 h. The solvent was removed in vacuo, and the residue was taken up in Et2O (25 mL) and 0.5 M NaHCO3 solution (50 mL). The layers were separated, and the aqueous layer was extracted with Et2O (10 mL). The combined organic layers were washed with H2O (10 mL). The pH of the combined aqueous layers was adjusted to pH 2 with HCl (0.5 M), and the aqueous solution was extracted with ethyl acetate. The combined organic layers were then dried with MgSO4 and concentrated to give the desired product 14 (1.55 g, 70 %)."