Pure crystalline plicatic acid tetrahydrate and the methyl ester thereof
Abstract
Abstract PURE CRYSTALLINE PLICATIC ACID TETRAHYDRATE THAT IS STABLE TO HEAT AND LIGHT UP TO ITS MELTING POINT OF 176*C. IS PREPARED FROM SUBSTANTIALLY PURE METHYL PLICATATE. THE PURE METHYL PLICATATE, WHICH IS ITSELF A NEW COMPOSITION OF MATTER CONVENIENTLY PREPARED FROM AN AQUEOUS EXTRACT OF RED CEDAR HEARTWOOD, IS SAPONIFIED WITH AN AQUEOUS SOLUTION OF ALKALI METAL HYDROXIDE AT AN ELEVATED TEMPERATURE UNDER SUBSTANTIALLY NON-OXIDATIVE CONDITIONS. THE RESULTING ALKALI METAL PLICATATE SOLUTION IS THEN ACIDIFIED WITH A SLIGHT EXCESS OF A MINERAL ACID SUCH AS HYDROCHLORIC OR SULFURIC ACID, AND THE ACIDIFIED SOLUTION IS COOLED, AND IF DESIRED SEEDED, WHEREUPON PURE CRYSTALLINE PLICATIC ACID TETRAHYDRATE PRECIPITATES IN YIELDS AS HIGH AS 80 OR 90 PERCENT OF THEORETICAL.
Inventors
- 👤 J Howard
- 👤 T Mcintosh
Bibliographic Details
Claims Analysis
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