Patent ID: 9120733
Filing Date: 2015-09-01
Classification: C07C

Abstract:
1. A process for obtaining pharmaceutical grade, storage-stable sevoflurane comprising: i) providing a crude sevoflurane product; ii) providing distillation equipment comprising surfaces that will come into contact with sevoflurane during distillation of the crude sevoflurane product, said surfaces being selected from the group consisting of stainless steel surfaces that resist forming metal salts; iii) passivating said surfaces with a passivation agent consisting of nitric acid or a mixture of nitric acid and sodium dichromate to yield passivated distillation equipment; iv) distilling the crude sevoflurane product in the passivated distillation equipment without adding sevoflurane decomposition suppressive agents; and v) recovering pharmaceutical grade, storage-stable sevoflurane as a distillate as a result of said distilling.