6-Bromo-3,4-dihydro-2H-benzo[1,4]oxazine hydrochloride

6-Bromo-3,4-dihydro-2H-benzo[1,4]oxazine hydrochloride Property

Boiling point:

296.4±40.0 °C(Predicted)

Density 

1.534±0.06 g/cm3(Predicted)

storage temp. 

Keep in dark place,Inert atmosphere,Room temperature

form 

solid

pka

3.59±0.20(Predicted)

Appearance

Light brown to orange Solid-liquid mixture

InChI

InChI=1S/C8H8BrNO/c9-6-1-2-8-7(5-6)10-3-4-11-8/h1-2,5,10H,3-4H2

InChIKey

RWKBNMSHIJBNAO-UHFFFAOYSA-N

SMILES

O1C2=CC=C(Br)C=C2NCC1

Safety

Hazard Codes 

Xn

Risk Statements 

22

HS Code 

2934999090

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Warning

Hazard statements

H302Harmful if swallowed

H315Causes skin irritation

H319Causes serious eye irritation

H335May cause respiratory irritation

Precautionary statements

P261Avoid breathing dust/fume/gas/mist/vapours/spray.

P304+P340IF INHALED: Remove victim to fresh air and Keep at rest in a position comfortable for breathing.

P305+P351+P338IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing.

P405Store locked up.

6-Bromo-3,4-dihydro-2H-benzo[1,4]oxazine hydrochloride Chemical Properties,Usage,Production

Uses

6-Bromo-3,4-dihydro-2H-1,4-benzoxazine is a reactant used for the synthesis of N-dichloroacetyl-3,4-dihydro-2H-1,4-benzoxazine derivatives.

Synthesis

General procedure for the synthesis of 6-bromo-3,4-dihydro-2H-benzo[1,4]oxazines from 6-bromo-2H-1,4-benzoxazin-3(4H)-ones: at room temperature, the borane-tetrahydrofuran complex (13.2 mL of a 1 M solution of tetrahydrofuran, 13.2 mmol) was added batchwise to intermediate 6 (2.0 g, 8.0 mmol) in a tetrahydrofuran ( 50 mL) solution. The reaction mixture was stirred for 10 minutes at room temperature and then heated to reflux for 1 hour, followed by cooling to room temperature. The reaction mixture was cooled in an ice bath and the reaction was quenched sequentially with water (20 mL) and 2 N aqueous sodium hydroxide solution (20 mL). The solvent was removed by rotary evaporator and the resulting mixture was diluted with water (100 mL). The aqueous phase was extracted with ethyl acetate (100 mL), the organic phase was washed with saturated brine (100 mL), dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure to give 6-bromo-3,4-dihydro-2H-benzo[1,4]oxazine as a brown oil (2 g, quantitative yield). NMR hydrogen spectrum (DMSO-d6) δ: 3.36-3.44 (2H, multiple peaks), 3.81 (1H, broad single peak), 4.18-4.25 (2H, multiple peaks), 6.68 (3H, multiple peaks).

References

[1] Patent: WO2008/44022, 2008, A1. Location in patent: Page/Page column 29
[2] Patent: WO2008/47109, 2008, A1. Location in patent: Page/Page column 50-51
[3] Patent: WO2009/71895, 2009, A1. Location in patent: Page/Page column 97-98
[4] Patent: WO2009/71888, 2009, A1. Location in patent: Page/Page column 73
[5] Patent: WO2009/71890, 2009, A1. Location in patent: Page/Page column 103-104