Borylation Directed Borylation of Indoles Using Pyrazabole Electrophiles: A One‐Pot Route to C7‐Borylated‐Indolines
نویسندگان
چکیده
Pyrazabole ( 1 ) is a readily accessible diboron compound that can be transformed into ditopic electrophiles. In (and derivatives), the B∙∙∙B separation ca. 3 Å, appropriate for one boron centre bonding to N and C7 of indoles indolines. This suitable enables double E-H (E = N/C) functionalisation Specifically, activation with HNTf 2 generates an electrophile transforms N-H indolines N/C7-diborylated indolines, borylation directing subsequent C7-H borylation. Indole reduction indoline occurs before C-H our studies indicate this proceeds via hydroboration - C3-protodeboronation produce intermediate then undergoes The borylated products converted in-situ C7-BPin-N-H-indolines. Overall, represents transient directed form useful C7-BPin-indolines.
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ژورنال
عنوان ژورنال: Angewandte Chemie
سال: 2022
ISSN: ['1521-3773', '1433-7851', '0570-0833']
DOI: https://doi.org/10.1002/ange.202206230