ChemicalBook CAS DataBase List tert-butyl benzo[b]thiophen-2-ylcarbaMate

tert-butyl benzo[b]thiophen-2-ylcarbaMate synthesis

5synthesis methods

Product Name:tert-butyl benzo[b]thiophen-2-ylcarbaMate
CAS Number:89673-36-9
Molecular formula:C13H15NO2S
Molecular Weight:249.33

6314-28-9

75-65-0

tert-butyl benzo[b]thiophen-2-ylcarbaMate

89673-36-9

Benzo[b]thiophene-2-carboxylic acid (1-A, 14.4 g, 80.6 mmol) was used as starting material and mixed with N,N-diisopropylethylamine (15.5 mL, 88.6 mmol) and diphenylphosphoryl azide (20.8 mL, 96.7 mmol) in tert-butanol (150 mL). The reaction mixture was heated to reflux for 8 hours. Upon completion of the reaction, the solvent was removed by vacuum evaporation. The resulting residue was purified by silica gel fast column chromatography using dichloromethane as eluent to afford the target product tert-butyl benzo[b]thiophene-2-yl-carbamate (1-B) as a colorless solid (18.9 g, 94% yield). The structure of the product was confirmed by 1H-NMR (DMSO-d6) and mass spectrometry (MS): 1H-NMR (DMSO-d6) δ 1.50 (s, 9H), 6.78 (s, 1H), 7.16 (d, J=7.5Hz, 1H), 7.27 (d, J=7.5Hz, 1H), 7.58 (d, J=7.5Hz, 1H), 7.77 ( d, J=7.5Hz, 1H), 10.70 (br s, 1H); MS: m/z 250.2 (MH+).

6314-28-9
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$21.00/5g

75-65-0 Synthesis

75-65-0
784 suppliers
$10.00/10ml

89673-36-9
52 suppliers
$11.00/100mg

Yield:89673-36-9 94%

Reaction Conditions:

with diphenyl phosphoryl azide;N-ethyl-N,N-diisopropylamine for 8 h;Heating / reflux;

Steps:

1

Benzo[Z>]thiophen-2-yl-carbamic acid tert-butyl ester (1-B).; A solution of compound 1-A (14.4 g, 80.6 mmol), N,N-diisopropylethylamine (15.5 mL, 88.6 mmol) and diphenylphosphoryl azide (20.8 mL, 96.7 mmol) in -butanol (150 mL) was heated at reflux for 8 h. The solvent was evaporated in vacuo, and the residue purified by flash column chromatography on silica gel, eluting with dichloromethane, to afford compound 1-B as a colorless solid (18.9 g, 94%). ¹H-NMR (DMSO-^): δ 1.50 (s, 9H), 6.78 (s, IH), 7.16 (d of d, IH), 7.27 (d of d, IH), 7.58 (d, IH), 7.77 (d, IH), 10.70 (br s, IH); MS: m/z 250.2 (MH⁺).

References:

WO2009/12430,2009,A1 Location in patent:Page/Page column 180-181