(-)-2,3-O-Isopropylidene-D-threitol

(-)-2,3-O-Isopropylidene-D-threitol Property

Melting point:

48-51 °C(lit.)

Boiling point:

91-93 °C0.01 mm Hg(lit.)

alpha 

-3.1 º (c=5, CHCl3 26 ºC)

Density 

1.0585 (rough estimate)

refractive index 

-4 ° (C=5, Acetone)

Flash point:

>230 °F

storage temp. 

Inert atmosphere,Store in freezer, under -20°C

solubility 

Chloroform, Dichloromethane, Ethyl Acetate, THF

pka

13.90±0.10(Predicted)

form 

Oil

color 

Yellow

Water Solubility 

Soluble in water.

Sensitive 

Hygroscopic

BRN 

1798

CAS DataBase Reference

73346-74-4(CAS DataBase Reference)

Safety

Hazard Codes 

Xn

Risk Statements 

20/21/22-36/37/38

Safety Statements 

22-24/25-36-26

WGK Germany 

3

F 

3-10

HS Code 

29329970

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.

P301+P312IF SWALLOWED: call a POISON CENTER or doctor/physician IF you feel unwell.

P302+P352IF ON SKIN: wash with plenty of soap and water.

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.

(-)-2,3-O-Isopropylidene-D-threitol Chemical Properties,Usage,Production

Chemical Properties

Colorless to light yellow liqui

Uses

(-)-2,3-O-Isopropylidene-D-threitol is used in the synthesis of the optically active enantiomorphic 2,3-butanediols. It react with toluene-4-sulfonyl chloride to get O2,O3-isopropylidene-O1,O4-bis-(toluene-4-sulfonyl)-D-threitol.

Synthesis

General procedure for the synthesis of 2,3-O-isopropylidene-D-sitosterol from dimethyl (4R,5R)-2,2-dimethyl-1,3-dioxolane-4,5-dicarboxylate: an anhydrous tetrahydrofuran (120 ml) solution of lithium aluminium hydride (10 g, 267 mmol) was stirred and refluxed under nitrogen protection for 30 min. Subsequently, a solution of anhydrous tetrahydrofuran (200 ml) of 2,3-O-isopropylidene-L-tartaric acid dimethyl ester (53 g, 243 mmol) was slowly added dropwise with stirring, and heat generated during the reaction induced a mild reflux. After continuing the reflux reaction for 3 h, the reaction solution was cooled to 0 °C. Water (8.4 ml), 4M sodium hydroxide solution (8.4 ml) and water (32 ml) were added sequentially to the reaction solution. The resulting precipitate was removed by filtration and the filtrate was extracted with ether (using Soxhlet extractor). The organic phases were combined, dried and concentrated under reduced pressure to give 2,3-O-isopropylidene-L-sitosterol (35 g, 216 mmol, 89% yield). The product was identified by 1H NMR (CDCl3): δ 3.98 (m, 2H), 3.77 (m, 4H), 3.64 (s, 2H), 1.45 (s, 6H); 13C NMR (CDCl3) showed the characteristic peaks: δ 109.53, 78.24, 62.25, 27.28; low resolution electron bombardment mass spectrometry (LREIMS) revealed that molecular ion peak m/z 162.1 (M+). The crude product obtained can be directly used in the subsequent reaction.

References

[1] Chirality, 2018, vol. 30, # 4, p. 342 - 350
[2] Angewandte Chemie - International Edition, 2008, vol. 47, # 20, p. 3762 - 3765
[3] European Journal of Organic Chemistry, 2011, # 23, p. 4465 - 4471
[4] Heterocycles, 2012, vol. 86, # 1, p. 687 - 695
[5] Journal of Organic Chemistry, 2016, vol. 81, # 22, p. 10698 - 10706