title: Operationally simple and efficient workup procedure for TBAF-mediated desilylation: application to halichondrin synthesis.
abstract: An operationally simple and efficient workup method for tetrabutylammonium fluoride (TBAF)-mediated t-butyldimethylsilyl (TBS) deprotection has been developed. The procedure includes addition of a sulfonic acid resin and calcium carbonate, followed by filtration and evaporation. This method eliminates the tedious aqueous-phase extraction process to remove excess TBAF and materials derived from TBAF, thereby making the protocol highly amenable to multiple TBS deprotections. Its efficiency and usefulness were demonstrated by using the transformation of 1a to 3a in the halichondrin synthesis. [reaction: see text].
authors.affiliation: Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA.
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Kaburagi
authors.forename: Yoshito
authors.initials: Y
authors.lastname: Kishi
mesh_terms: D002119:Calcium Carbonate; D004988:Ethers, Cyclic / Q000138:chemical synthesis*; D005374:Filtration; D007202:Indicators and Reagents; D007475:Ion Exchange Resins; D018942:Macrolides; D009682:Magnetic Resonance Spectroscopy; D000644:Quaternary Ammonium Compounds / Q000737:chemistry*; D013451:Sulfonic Acids / Q000737:chemistry; D000095662:Polyether Polyketides
chemical_list: D002119:Calcium Carbonate; D004988:Ethers, Cyclic; D007202:Indicators and Reagents; D007475:Ion Exchange Resins; D018942:Macrolides; D000644:Quaternary Ammonium Compounds; D013451:Sulfonic Acids; C070519:halichondrin B; D000095662:Polyether Polyketides; C009405:tetrabutylammonium