B−B bond nucleophilicity in a tetraaryl μ‐hydridodiborane(4) anion
- The tetraaryl μ‐hydridodiborane(4) anion [2H]− possesses nucleophilic B−B and B−H bonds. Treatment of K[2H] with the electrophilic 9‐H‐9‐borafluorene (HBFlu) furnishes the B3 cluster K[3], with a triangular boron core linked through two BHB two‐electron, three‐center bonds and one electron‐precise B−B bond, reminiscent of the prominent [B3H8]− anion. Upon heating or prolonged stirring at room temperature, K[3] rearranges to a slightly more stable isomer K[3 a]. The reaction of M[2H] (M+=Li+, K+) with MeI or Me3SiCl leads to equimolar amounts of 9‐R‐9‐borafluorene and HBFlu (R=Me or Me3Si). Thus, [2H]− behaves as a masked [:BFlu]− nucleophile. The HBFlu by‐product was used in situ to establish a tandem substitution‐hydroboration reaction: a 1:1 mixture of M[2H] and allyl bromide gave the 1,3‐propylene‐linked ditopic 9‐borafluorene 5 as sole product. M[2H] also participates in unprecedented [4+1] cycloadditions with dienes to furnish dialkyl diaryl spiroborates, M[R2BFlu].
Author: | Timo TrageserGND, Michael BolteORCiD, Hans-Wolfram LernerORCiDGND, Matthias WagnerORCiD |
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URN: | urn:nbn:de:hebis:30:3-564987 |
DOI: | https://doi.org/10.1002/anie.202000292 |
ISSN: | 1521-3773 |
ISSN: | 1433-7851 |
Parent Title (German): | Angewandte Chemie. International edition |
Publisher: | Wiley-VCH |
Place of publication: | Weinheim |
Document Type: | Article |
Language: | English |
Date of Publication (online): | 2020/02/14 |
Date of first Publication: | 2020/02/14 |
Publishing Institution: | Universitätsbibliothek Johann Christian Senckenberg |
Release Date: | 2020/12/09 |
Volume: | 59 |
Issue: | 20 |
Page Number: | 6 |
First Page: | 7726 |
Last Page: | 7731 |
HeBIS-PPN: | 476111412 |
Institutes: | Biochemie, Chemie und Pharmazie / Biochemie und Chemie |
Dewey Decimal Classification: | 5 Naturwissenschaften und Mathematik / 54 Chemie / 540 Chemie und zugeordnete Wissenschaften |
Sammlungen: | Universitätspublikationen |
Licence (German): | Creative Commons - Namensnennung-Nicht kommerziell - Keine Bearbeitung 4.0 |