1.1
Reagents:
Pyridine
Solvents:
Dichloromethane
;
-20 °C; 2 h, rt
2.1
Reagents:
Triethylamine trihydrofluoride
;
2 h, 80 °C
3.1
Reagents:
Pyridine
Solvents:
Methanol
,
Tetrahydrofuran
;
3 h, rt; 50 °C