1,2-BIS[(DIMETHYLAMINO)DIMETHYLSILYL]ETHANE Property

Boiling point:

101-103 °C13 mm Hg(lit.)

Density 

0.824 g/mL at 25 °C(lit.)

refractive index 

n20/D 1.446(lit.)

Flash point:

57 °F

pka

10.31±0.70(Predicted)

form 

clear liquid

color 

Colorless to Almost colorless

Specific Gravity

0.824

Hydrolytic Sensitivity

8: reacts rapidly with moisture, water, protic solvents

BRN 

4366167

CAS DataBase Reference

91166-50-6(CAS DataBase Reference)

Safety

Hazard Codes 

F,C

Risk Statements 

11-34

Safety Statements 

16-26-36/37/39-45

RIDADR 

UN 2924 3/PG 2

WGK Germany 

3

F 

10-21

TSCA 

No

HazardClass 

3.1

PackingGroup 

II

HS Code 

29319019

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Danger

Hazard statements

H225Highly Flammable liquid and vapour

H314Causes severe skin burns and eye damage

Precautionary statements

P210Keep away from heat/sparks/open flames/hot surfaces. — No smoking.

P233Keep container tightly closed.

P240Ground/bond container and receiving equipment.

P260Do not breathe dust/fume/gas/mist/vapours/spray.

P264Wash hands thoroughly after handling.

P264Wash skin thouroughly after handling.

P280Wear protective gloves/protective clothing/eye protection/face protection.

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

P310Immediately call a POISON CENTER or doctor/physician.

P403+P235Store in a well-ventilated place. Keep cool.

P405Store locked up.

P501Dispose of contents/container to..…

1,2-BIS[(DIMETHYLAMINO)DIMETHYLSILYL]ETHANE Chemical Properties,Usage,Production

Physical properties

bp 100–103°C/13 mmHg; d 0.824 g cm?3.

Uses

1,4-Bis(dimethylamino)-1,1,4,4-tetramethyldisilethylene is used as a reagent for the protection of primary amines with lower pKa values, such as substituted anilines, as their tetramethyldisilylazacyclopentane or Stabase adduct; precursor of tetramethyldisilylthiacyclopentane, a sulfur transfer reagent.
The title reagent is used for the preparation of Stabase derivatives of primary amines, and is particularly useful for the protection of primary aromatic amines with pKa values of 10–11. The protection of substituted anilines is achieved by heating equimolar amounts of the title compound and the anilines in the presence of zinc iodide (0.5 mol %) under a slow stream of nitrogen at 140°C for 5 h. In many cases the products can be purified by vacuum distillation. Cleavage of the Stabase adducts to the corresponding primary amines can be performed in ether in the presence of 2 equiv of methanol and a small amount of p-toluenesulfonic acid monohydrate (0.2 mol %). The tetramethyldisilylazacyclopentane or Stabase adduct (3) is a particularly attractive protecting group due to its ease of preparation, base stability, and facile removal (eq 1).

Preparation

the reagent is prepared as a colorless liquid in 90% yield by treating commercially available bis(chlorodimethylsilyl) ethane with 5 equiv of dimethylamine in ether at 0°C for 5 h.