Bis(tert-butyl)carbodiimide
[CAS# 691-24-7]

Identification

• Classification: Chemical reagent >> Organic reagent >> Imide
• Name: Bis(tert-butyl)carbodiimide
• Synonyms: 1,3-Di-tert-butylcarbodiimide; Di-tert-butylcarbodiimide; N,N'-Di-tert-butylcarbodiimide
• Molecular Formula: C₉H₁₈N₂
• Molecular Weight: 154.25
• CAS Registry Number: 691-24-7
• EC Number: 211-719-6
• SMILES: CC(C)(C)N=C=NC(C)(C)C

Properties

• Solubility: Very slightly soluble (0.26 g/L) (25 ºC), Calc.^*
• Density: 0.80±0.1 g/cm³ (20 ºC 760 Torr), Calc.^*
• Index of Refraction: 1.428
• Boiling point: 140 ºC (1 Torr)^**
• Flash point: 35.0±0.0 ºC, Calc.^*

^* Calculated using Advanced Chemistry Development (ACD/Labs) Software V11.02 (©1994-2015 ACD/Labs)

^** Smeltz, Kenneth C.; US 3157662 1964.

Safety Data

• Hazard Symbols: GHS02;GHS07 Warning
• Hazard Statements: H226-H315-H319-H335
• Precautionary Statements: P210-P233-P240-P241-P242-P243-P261-P264-P264+P265-P271-P280-P302+P352-P303+P361+P353-P304+P340-P305+P351+P338-P319-P321-P332+P317-P337+P317-P362+P364-P370+P378-P403+P233-P403+P235-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Skin irritation	Skin Irrit.	2	H315
Flammable liquids	Flam. Liq.	3	H226
Eye irritation	Eye Irrit.	2	H319
Specific target organ toxicity - single exposure	STOT SE	3	H335
Eye irritation	Eye Irrit.	2A	H319

• Transport Information: UN 1993C 3 / PGIII

Discovory and Applicatios

Bis(tert-butyl)carbodiimide, commonly referred to as BTC, is a chemical compound characterized by its unique structure and reactivity, making it an essential reagent in organic synthesis. The compound features a central carbon atom bonded to two tert-butyl groups and a carbodiimide functional group, which consists of two nitrogen atoms connected by a carbon atom. The discovery of bis(tert-butyl)carbodiimide can be traced back to the development of carbodiimide chemistry in the mid-20th century. The first synthesis of simple carbodiimides was reported in the 1940s, and subsequent work led to the derivation of more complex carbodiimides, including BTC, to improve the efficiency and selectivity of peptide coupling reactions.

One of the primary applications of bis(tert-butyl)carbodiimide lies in the field of peptide synthesis. Carbodiimides, including BTC, are commonly used as coupling agents for activating carboxylic acids, facilitating their reaction with amines to form amides or peptides. This reactivity is particularly valuable in the synthesis of complex peptides and proteins, where high yields and selective coupling are essential. The sterically bulky tert-butyl groups in BTC provide enhanced selectivity and stability, making it a preferred choice over other coupling agents in certain reactions.

In addition to its use in peptide synthesis, bis(tert-butyl)carbodiimide has found applications in various areas of organic synthesis, including the formation of esters and amides from carboxylic acids and alcohols or amines. Its ability to promote condensation reactions under mild conditions and without the need for strong acids or bases makes it a versatile tool in synthetic organic chemistry. Furthermore, BTC is utilized in the functionalization of biomolecules and polymers, enhancing the range of applications in medicinal chemistry and materials science.

Despite its widespread use, handling bis(tert-butyl)carbodiimide requires caution due to its reactivity and potential hazards. The compound can cause irritation to the skin and eyes, and safety measures must be implemented to minimize exposure during laboratory procedures.

Research continues to explore the utility of bis(tert-butyl)carbodiimide in various chemical transformations and applications. Ongoing investigations focus on optimizing its use in peptide synthesis, improving reaction conditions, and discovering new applications in areas such as drug development and bioconjugation.

In summary, bis(tert-butyl)carbodiimide is a significant reagent in organic synthesis, particularly in peptide coupling reactions. Its discovery has enhanced the efficiency and selectivity of various chemical processes, making it an invaluable tool in the fields of medicinal chemistry and organic synthesis.