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Title: Regioselective Gas‐Phase n ‐Butane Transfer Dehydrogenation via Silica‐Supported Pincer‐Iridium Complexes
Abstract

The production of olefins via on‐purpose dehydrogenation of alkanes allows for a more efficient, selective and lower cost alternative to processes such as steam cracking. Silica‐supported pincer‐iridium complexes of the form [(≡SiO−R4POCOP)Ir(CO)] (R4POCOP=κ3‐C6H3‐2,6‐(OPR2)2) are effective for acceptorless alkane dehydrogenation, and have been shown stable up to 300 °C. However, while solution‐phase analogues of such species have demonstrated high regioselectivity for terminal olefin production under transfer dehydrogenation conditions at or below 240 °C, in open systems at 300 °C, regioselectivity under acceptorless dehydrogenation conditions is consistently low. In this work, complexes [(≡SiO−tBu4POCOP)Ir(CO)] (1) and [(≡SiO−iPr4PCP)Ir(CO)] (2) were synthesized via immobilization of molecular precursors. These complexes were used for gas‐phase butane transfer dehydrogenation using increasingly sterically demanding olefins, resulting in observed selectivities of up to 77 %. The results indicate that the active site is conserved upon immobilization.

 
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Award ID(s):
1705746
PAR ID:
10236534
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
ChemCatChem
Volume:
13
Issue:
1
ISSN:
1867-3880
Page Range / eLocation ID:
p. 407-415
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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