title: NH₄HF₂ as a selective TBS-removal reagent for the synthesis of highly functionalized spiroketal via tandem deprotection/spiroketalization procedure.
abstract: NH4HF2 has been used for the first time to selectively remove the TBS protecting groups from diol ketone precursors in the synthesis of highly functionalized spiroketals. This method allows the synthesis of [5,6], [6,6], and [6,7] spiroketal skeletons, as well as benzannulated spiroketal with retention of acid-sensitive groups. In this way, spiroketals can be synthesized with diverse substituent groups in the skeleton or on side chains. To demonstrate the utility of this methodology, the diverse transformations of highly functionalized spiroketal 3f were also investigated.
authors: State Key Laboratory of Applied Organic Chemistry and Department of Chemistry Lanzhou University , Lanzhou 730000, P. R. China.
authors: Hui
authors: H
authors: Lu
authors: Fu-Min
authors: FM
authors: Zhang
authors: Jin-Long
authors: JL
authors: Pan
authors: Tao
authors: T
authors: Chen
authors: Yi-Fan
authors: YF
authors: Li
mesh_terms: D064751:Ammonium Compounds; D005459:Fluorides / Q000737:chemistry*; D005663:Furans / Q000138:chemical synthesis* / Q000737:chemistry; D008968:Molecular Conformation; D000644:Quaternary Ammonium Compounds / Q000737:chemistry*; D012821:Silanes / Q000737:chemistry*; D013141:Spiro Compounds / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D064751:Ammonium Compounds; D005663:Furans; D000644:Quaternary Ammonium Compounds; D012821:Silanes; D013141:Spiro Compounds; C520774:spiroketal; C103256:tert-butyldimethylsilane; C024822:ammonium fluoride; D005459:Fluorides