5-(Ethylthio)-1H-tetrazole

Synonym(s):ETT;OCTN1;SLC22A4;UT2H;5-(Ethylthio)-1H-tetrazole

CAS NO.：89797-68-2
Empirical Formula: C3H6N4S
Molecular Weight: 130.17
MDL number: MFCD00068733
EINECS: 000-000-0
SAFETY DATA SHEET (SDS)
Update Date: 2025-09-25 17:15:13

What is 5-(Ethylthio)-1H-tetrazole?

Chemical properties

White crystals

What are the applications of Application

5-(Ethylthio)-1H-tetrazole is used a powerful activator in DNA and RNA syntheses.

Preparation

5-(Ethylthio)-1H-Tetrazole is prepared from the corresponding alkyl thiocyanate and sodium azide through a [2?+?3] cycloaddition under phase transfer catalytic conditions (eq 1). The ratio of the solvent (water to toluene) as well as the reaction temperature are important factors in obtaining preparative yields of the alkylthiotetrazoles. 5-Ethylthio-1H-tetrazole has also been prepared using DMF as solvent albeit in much lower yield.
synthesis of 5-(Ethylthio)-1H-tetrazole

General Description

5-(Ethylthio)-1H-tetrazole (ETT) is an efficient activator, that activates nucleoside phosphoramidites towards condensation with a nucleoside to form dinucleoside phosphates during oligonucleotide synthesis.

Purification Methods

recrystallized from toluene.

Properties of 5-(Ethylthio)-1H-tetrazole

Melting point:	72-80 °C(lit.)
Boiling point:	81-82 °C
Density	0.786 g/mL at 25 °C
Flash point:	42 °F
storage temp.	2-8°C
solubility	soluble, clear, colorless
form	buffered aqueous solution
pka	3.89±0.10(Predicted)
color	solid white
CAS DataBase Reference	89797-68-2(CAS DataBase Reference)

Safety information for 5-(Ethylthio)-1H-tetrazole

Signal word	Danger
Pictogram(s)	Flame Flammables GHS02 Corrosion Corrosives GHS05 Exclamation Mark Irritant GHS07
GHS Hazard Statements	H225:Flammable liquids H315:Skin corrosion/irritation H318:Serious eye damage/eye irritation
Precautionary Statement Codes	P210:Keep away from heat/sparks/open flames/hot surfaces. — No smoking. P280:Wear protective gloves/protective clothing/eye protection/face protection. P301+P312:IF SWALLOWED: call a POISON CENTER or doctor/physician IF you feel unwell. P303+P361+P353:IF ON SKIN (or hair): Remove/Take off Immediately all contaminated clothing. Rinse SKIN with water/shower. P305+P351+P338:IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing.