Isobutyl chloroformate

• Catalog No.: A14692
• CAS Number: 543-27-1
• M. F.: C5H9ClO2
• M. W.: 136.57676
• Purity: 98%

SYNONYMS

• Title: 氯甲酸异丁酯
• IUPAC name: 2-methylpropyl chloroformate
• IUPAC Traditional name: 2-methylpropyl chloroformate
• Synonyms: Chloroformic acid isobutyl ester

DATABASE IDS

• MDL Number: MFCD00000642
• Beilstein Number: 956590
• EC Number: 208-840-1
• Merck Index: 145139
• CAS Number: 543-27-1

PROPERTIES

• Purity: 98%
• Boiling Point: 128-129°C
• Density: 1.048
• Flash Point: 30°C(86°F)
• Melting Point: -80°C
• Refractive Index: 1.4060
• GHS Hazard statements: H300-H310-H330-H314-H318-H226
• European Hazard Symbols: Toxic (T)
• GHS Precautionary statements: P210-P301+P310-P303+P361+P353-P304+P340-P305+P351+P338-P320-P330-P361-P405-P501A
• Risk Statements: 10-23/24/25-34
• Safety Statements: 9-23-26-27-36/37/39-45-60
• Storage Warning: Moisture Sensitive
• TSCA Listed: 是
• Hazard Class: 6.1
• UN Number: UN2742
• Packing Group: II

REFERENCES

• Superior to ethyl chloroformate in the mixed anhydride method of peptide synthesis: Org. Prep. Proced. Int., 7, 215 (1975); review: Org. React., 12, 157 (1962). Use in combination with 1-Methylpiperidine, L03398, minimizes competing urethane formation, arising from cleavage of the mixed anhydride in the wrong sense: J. Org. Chem., 48, 2939 (1983). Addition of CuCl₂ is reported to suppress racemization completely: Chem. Lett., 2125 (1989). For peptide reagents, see Appendix 6.
• Has been used to protect a nucleoside OH group as its isobutyl carbonate. Cleavage was by hydrolysis with 80% AcOH: J. Org. Chem., 32, 2365 (1967). Protection of amino groups as their isobutyl carbamates has also been reported: J. Am. Chem. Soc., 91, 3356 (1969).