Chemoselective hydrogenation of 17α-hydroxy-6-methylen-pregna-4,9(11)-diene-3,20-dione. Synthesis of fluorometholone
摘要:
The development of an efficient hydrogenation method of 17 alpha-hydroxy-6-methylen-pregna-4,9(11)-diene-3,20-dione by using wet (10%) Pd on carbon and triethylamine led us to the corresponding 6 alpha-methyl-pregnane in good yield. This chemoselective process allowed us to set up a large-scale procedure for the synthesis of the ophthalmic drug fluorometholone with 45% overall yield. (C) 2009 Elsevier Ltd. All rights reserved.
This invention relates to processes for base catalyzed acylations using enol esters, for example, isopropenyl acetate. Particularly, the processes are useful for acylating acid sensitive alcohols including hydroxy steroids.
Chemoselective hydrogenation of 17α-hydroxy-6-methylen-pregna-4,9(11)-diene-3,20-dione. Synthesis of fluorometholone
作者:Andrés Marcos-Escribano、Francisco A. Bermejo、Antonio Lorente Bonde-Larsen、Jesús Iglesias Retuerto
DOI:10.1016/j.tet.2009.08.030
日期:2009.10
The development of an efficient hydrogenation method of 17 alpha-hydroxy-6-methylen-pregna-4,9(11)-diene-3,20-dione by using wet (10%) Pd on carbon and triethylamine led us to the corresponding 6 alpha-methyl-pregnane in good yield. This chemoselective process allowed us to set up a large-scale procedure for the synthesis of the ophthalmic drug fluorometholone with 45% overall yield. (C) 2009 Elsevier Ltd. All rights reserved.