Reaktion #2444263

Reaktionsgleichung

phenol

(R)-tert-Butyl 2,2,4-trimethyl-4-(2-(4-(octyloxy)-3-(trifluoromethyl)phenyl)-2-oxoethylcarbamoyl)oxazolidine-3-carboxylate

thiazole

→

intermediate 7

(R)-tert-Butyl 2,2,4-trimethyl-4-(5-(4-(octyloxy)-3-(trifluoromethyl)phenyl)thiazol-2-yl)oxazolidine-3-carboxylate

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeRemoval of PMB group under hydrogenation
2. 2
   Sonstigegave phenol 6

Vorschrift

The synthesis of 2,5-substituted thiazoles is described in Scheme 9. Reaction of the desired alcohol para-methoxybenzyl alcohol (PMB-OH) with substituted 4-fluoroacetophenone 1 afforded the acetophenone intermediate 2. Acetophenone intermediate 2 was then converted to the corresponding bromo-acetophenone using Bu4NBr3 which, upon reaction with NaN3, provided the azido-acetophenone intermediate. Hydrogenation of the azido-acetophenone intermediate afforded amine 3, followed by coupling with orthogonally protected amino acid 4 gave amide 5. Removal of PMB group under hydrogenation gave phenol 6. Mitsunobu reaction of the phenol 6 with the desired alcohol followed by thiazole formation under Lawesson's reagent conditions afforded intermediate 7 in good yield. Removal of the protecting group from intermediate 7 afforded the final amino-alcohol 8.

Quelle