Electrophilic fluorosulfoxonium cations as hidden Brønsted acid catalysts in (<i>n</i> + 2) annulations of strained cycloalkanes
نویسندگان
چکیده
A fluorosulfoxonium cation and triflic acid were shown to promote ( n + 2) annulations of donor–acceptor cyclopropanes or -butanes with 1,2-dipoles, different activity selectivity but a presumed similar role as (hidden) Brønsted acids.
منابع مشابه
Ferrocenyl-derived electrophilic phosphonium cations (EPCs) as Lewis acid catalysts.
Oxidation of diphenylphosphinoferrocene and 1,1'-bis(diphenylphosphino)ferrocene with XeF2, resulted in the formation of CpFe(η(5)-C5H4PF2Ph2) 1 and Fe(η(5)-C5H4PF2Ph2)22 respectively. Subsequent reactions with [SiEt3][B(C6F5)4] yielded [CpFe(η(5)-C5H4PFPh2)][B(C6F5)4] 3 and [Fe(η(5)-C5H4PFPh2)2] [B(C6F5)4]24. PhP(η(5)-C5H4)2Fe 5 was prepared, converted to [PhMeP(η(5)-C5H4)2Fe][O3SCF3] 6 and th...
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ژورنال
عنوان ژورنال: Organic chemistry frontiers
سال: 2021
ISSN: ['2052-4110', '2052-4129']
DOI: https://doi.org/10.1039/d1qo00840d