Phosphorus pentachloride → 2,6-Dichlorobenzoxazole

Participants

Reaction Steps

400 ml of o-diohIorobenzene and 1,040 g (5 moles) of phosphorus pentachloride are heated to 150° to 160° C. Then 169.5 g (1 mole) of 6-chlorobenzoxazolin-2-one, suspended in 600 ml of o-dichlorobenzene, are metered in within 2 hours with heating such that the interior temperature does not drop below 150° C. The addition being complete, stirring is continued for a further 10 minutes. working up analogously to Example 8 results in a yield of 145 g of 2,6-dichlorobenzoxazole, corresponding to 77% of theory. GC purity: 99.7%.

Provenance & Evidence