Ethyl/butyl phosphonic acid Silica (PhosphonicS POH1)

Technical Note:
1. Applications include esterification, trans-esterification, hydrolysis, rearrangements, dehydration, protection and de-protection, cyclizations, etherifications. At the end of the reaction the solid silica catalyst can simply be filtered from the reaction mixture and reused.
Reference:
1. Org. Process Res. Dev., 2007, 11, 406