Abstract
| Language | English |
|---|---|
| Pages | 16853-16861 |
| Number of pages | 9 |
| Journal | Chemistry - A European Journal |
| Volume | 23 |
| Issue number | 66 |
| Early online date | 21 Sep 2017 |
| DOIs | |
| Publication status | Published - 27 Nov 2017 |
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Keywords
- soluble hydride surrogates
- 1-lithium-2-t-butyl-1,2-dihydropyridine
- 1tLi
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1-Alkali-metal-2-alkyl-1,2-dihydropyridines : soluble hydride surrogates for catalytic dehydrogenative coupling and hydroboration applications. / McLellan, Ross; Kennedy, Alan R.; Mulvey, Robert E.; Orr, Samantha A.; Robertson, Stuart D.
In: Chemistry - A European Journal, Vol. 23, No. 66, 27.11.2017, p. 16853-16861.Research output: Contribution to journal › Article
TY - JOUR
T1 - 1-Alkali-metal-2-alkyl-1,2-dihydropyridines
T2 - Chemistry - A European Journal
AU - McLellan, Ross
AU - Kennedy, Alan R.
AU - Mulvey, Robert E.
AU - Orr, Samantha A.
AU - Robertson, Stuart D.
N1 - This is the peer reviewed version of the following article: McLellan, R., Kennedy, A. R., Mulvey, R. E., Orr, S. A. and Robertson, S. D. (), 1-Alkali-metal-2-alkyl-1,2-dihydropyridines: soluble hydride surrogates for catalytic dehydrogenative coupling and hydroboration applications. Chem. Eur. J., which has been published in final form at https://doi.org/10.1002/chem.201703609. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.
PY - 2017/11/27
Y1 - 2017/11/27
N2 - Equipped with excellent hydrocarbon solubility, the lithium hydride surrogate 1-lithium-2-t-butyl-1,2-dihydropyridine (1tLi) functions as a precatalyst to convert Me2NH·BH3 to [NMe2BH2]2 (89% conversion) under competitive conditions (2.5 mol%, 60h, 80°C, toluene solvent) to that of previously reported LiN(SiMe3)2. Sodium and potassium dihydropyridine congeners produce similar high yields of [NMe2BH2]2 but require longer times. Switching the solvent to pyridine induces a remarkable change in the dehydrocoupling product ratio, with (NMe2)2BH favoured over [NMe2BH2]2 (e.g., 94%:2% for 1tLi). Demonstrating its versatility, precatalyst 1tLi was also successful in promoting hydroboration reactions between pinacolborane and a selection of aldehydes and ketones. Most reactions gave near quantitative conversion to the hydroborated products in 15 minutes, though sterically demanding carbonyl substrates require longer times. The mechanisms of these rare examples of group 1 metal catalysed processes are discussed.
AB - Equipped with excellent hydrocarbon solubility, the lithium hydride surrogate 1-lithium-2-t-butyl-1,2-dihydropyridine (1tLi) functions as a precatalyst to convert Me2NH·BH3 to [NMe2BH2]2 (89% conversion) under competitive conditions (2.5 mol%, 60h, 80°C, toluene solvent) to that of previously reported LiN(SiMe3)2. Sodium and potassium dihydropyridine congeners produce similar high yields of [NMe2BH2]2 but require longer times. Switching the solvent to pyridine induces a remarkable change in the dehydrocoupling product ratio, with (NMe2)2BH favoured over [NMe2BH2]2 (e.g., 94%:2% for 1tLi). Demonstrating its versatility, precatalyst 1tLi was also successful in promoting hydroboration reactions between pinacolborane and a selection of aldehydes and ketones. Most reactions gave near quantitative conversion to the hydroborated products in 15 minutes, though sterically demanding carbonyl substrates require longer times. The mechanisms of these rare examples of group 1 metal catalysed processes are discussed.
KW - soluble hydride surrogates
KW - 1-lithium-2-t-butyl-1,2-dihydropyridine
KW - 1tLi
UR - http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)1521-3765
U2 - 10.1002/chem.201703609
DO - 10.1002/chem.201703609
M3 - Article
VL - 23
SP - 16853
EP - 16861
JO - Chemistry - A European Journal
JF - Chemistry - A European Journal
SN - 0947-6539
IS - 66
ER -