HazMat Tool — substance information

Trimethyl borate

HMT May 2026
UN / ID
UN 2416
Hazard class
3
Packing group
II
ERG guide
ERG 129
Special provisions
SP IB2, SP T7, SP TP1
Source
49 CFR §172 (2026/05)

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Trimethyl borate


Trimethyl borate is the organoboron compound with the formula B(OCH3)3. It is a colourless liquid that burns with a green flame. It is an intermediate in the preparation of sodium borohydride and is a popular reagent in organic chemistry. It is a weak Lewis acid (AN = 23, Gutmann-Beckett method). Borate esters are prepared by heating boric acid or related boron oxides with alcohols under conditions where water is removed by azeotropic distillation. Wikipedia

Substance Data

Source: PubChem

CAS-Number

121-43-7

Flash Point

n/a

Boiling Point

n/a

Emergency Response Guide No. 129

Hazardous Materials Table

Source: 49 CFR §172 (2026/05)

(3) Hazard Class

3
Flammable liquids

(4) Identification number Help

UN 2416

(5) Packing Group Help

II

(6) Labels Help

Flammable liquids (3)

(7) Special Provisions (§172.102) Help

×Note:
Special provisions may be very complex. The extracts are taken from 49 CFR §172.102. Please be careful with the information, as necessary, additional conditions may be applied that are not written here. Please check the original source and report bugs.
IB2
T7
TP1

(8) Packing Authorizations (§173.***) Help

(8A) Exceptions150see 49 CFR §173.150
(8B) Non-bulk202see 49 CFR §173.202
(8C) Bulk242see 49 CFR §173.242

(9) Quantity Limits Help

(9A) Passenger aircraft/rail5 L
(9B) Cargo aircraft only60 L

(10) Vessel stowage Help

(10A) Location
(10B) Other n/a

Segregation chart for load, transport, and storage

This chart shows whether loading, transport, or storage with other hazard classes is permitted, prohibited, or restricted. Based on 49 CFR §177.848.

Prohibited Must not be loaded, transported, or stored together in the same vehicle or facility.
Permitted May be loaded, transported, or stored together.
Restricted May be loaded, transported, or stored together only with restrictions.