Sodium hydride

• Catalog No.: 13431
• CAS Number: 7646-69-7
• M. F.: Na+
• M. W.: 22.98977
• Purity: 57-63% oil dispersion

SYNONYMS

• Title: 氢化钠
• IUPAC name: sodium hydride
• IUPAC Traditional name: sodium hydride

DATABASE IDS

• MDL Number: MFCD00003471
• CAS Number: 7646-69-7
• Merck Index: 148625
• EC Number: 231-587-3

PROPERTIES

• Purity: 57-63% oil dispersion
• Apperance: Powder
• Density: 0.92
• Melting Point: 800°C dec.
• GHS Hazard statements: H260
• European Hazard Symbols: Flammable (F)
• GHS Precautionary statements: P231+P232-P280-P233-P370+P378I-P402+P404-P501A
• Risk Statements: 15
• Safety Statements: 7/8-24/25-43
• Storage Warning: Air & Moisture Sensitive
• TSCA Listed: 是
• Hazard Class: 4.3
• UN Number: UN1427
• Packing Group: I

REFERENCES

• Used in the deprotonation of DMSO to form "dimsyl sodium", a useful strong base for e.g. the Wittig reaction: J. Org. Chem., 28, 1128 (1963).
• For a review of sodium hydride-based complex reducing agents, see: Acta Chem. Scand., 44, 274 (1990).
• Widely used strong base for the irreversible formation of Na derivatives. If required, the protective oil can be removed by repeated washing and decantation with low-boiling petroleum, see, e.g.: Org. Synth. Coll., 6, 684 (1988), but for many purposes, this is not necessary, and the oil can be removed by incorporating a suitable extraction or washing step in the work-up. There are numerous Organic Syntheses references to reactions using NaH.
• CAUTION! Many literature procedures employ NaH in DMF, and this system is often used routinely by research workers as a 'convenient' general purpose strong base. It should be noted, especially when considering scale-up of such reactions, that thermal runaways have been observed with NaH/ DMF, with self-heating beginning at temperatures as low as 26^oC in some cases: Chem. Eng. News, 60(28), 5; 60(37), 5 (1982). A similar effect was also noted with N,N-dimethylacetamide. More recently also, incidents have been reported with other dipolar aprotic solvents 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone (DMPU) and Dimethyl sulfoxide (DMSO): Org. Process. Res. Dev., 7, 1030 (2003).