Hydrochloric Acid → 5-(2-(Tert-butyldimethylsilyloxy)ethyl)-2-chlorothiophene-3-carbaldehyde

tert-Butyl(2-(5-chlorothiophen-2-yl)ethoxy)dimethylsilane [Aromatic Intermediate 17, step a] (0.8 g) was added dropwise over 5 min to a stirred solution of butyllithium (2.5M in hexanes, 1.73 mL) and 2,2,6,6-tetramethylpiperidine (0.73 mL) in THF (25 mL) at −78° C. The resulting mixture was stirred for 2 h then DMF (0.67 mL) was added. The mixture was stirred for a further 1 h and allowed to warm to RT. The reaction mixture was cautiously poured into aqueous HCl (0.5M, 200 mL) and extracted with ethyl acetate (3×100 mL). The combined organic phases were washed with water (2×100 mL) and brine (100 mL), then dried over sodium sulphate, filtered and evaporated. The resulting oil was purified by silica gel chromatography eluting with isohexane to 5% ether in isohexane gradient. The fractions containing product were combined and evaporated to give the subtitled compound as a clear oil. Yield 0.80 g.

1. stirringThe mixture was stirred for a further 1 h
2. extractionextracted with ethyl acetate (3×100 mL)
3. washThe combined organic phases were washed with water (2×100 mL) and brine (100 mL)
4. dry with materialdried over sodium sulphate
5. filtrationfiltered
6. customevaporated
7. customThe resulting oil was purified by silica gel chromatography
8. washeluting with isohexane to 5% ether in isohexane gradient
9. additionThe fractions containing product
10. customevaporated

ORD-Eintrag

ord-7a8f4660e7a14919acd711fcbdaa18ea

Quelldatensatz

uspto-grants-2013_07

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08476265B2