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Delvos, L. B.; Oestreich, M., Science of Synthesis Knowledge Updates, (2017) 1, 102.
Amino-functionalized silylboronic ester 47 serves as a silylene precursor in palladium-catalyzed (4 + 1)-cycloaddition reactions with 1,3-dienes 97, giving access to a variety of silacyclopentenes 98, which are difficult to obtain by other methods (Scheme 44).[75] A catalyst screening revealed that bis(dibenzylideneacetone)palladium(0) and methyldiphenylphosphine as ligand are an optimal combination for this transformation. Substitution is allowed on every carbon atom of the diene, and several mono-, di-, and trisubstituted substrates form the corresponding silacyclopentenes 98 in good yields. Among other functional groups, even an alkene is compatible with the reaction conditions. A bulkier silylboron reagent with two phenyl groups at the silicon atom was used successfully at slightly higher reaction temperatures (50 °C), expanding the scope to cyclohexa-1,3-diene and gaseous buta-1,3-diene (not shown).
Meeeee 88 Meeeeeeee-Meeeeeeee (8 + 8) Meeeeeeeeeeee ee 8,8-Meeeee eeee e Meeeeeee[88]
| M8 | M8 | M8 | Meeee (%) | Mee |
|---|---|---|---|---|
| Me | M | M | 88e | [88] |
| M | M | Me | 88 | [88] |
| M | M | (MM8)8MM8Me | 88 | [88] |
| M | M | (MM8)8MM | 88 | [88] |
| M | M | (MM8)8MM=MMe8 | 88 | [88] |
| M | M | MMeMe8Me | 88e | [88] |
| Me | M | Me | 88e | [88] |
| Me | M | MMeMe8Me | 88e | [88] |
| M | (MM8)8Me | (MM8)8Me | 88 | [88] |
| M | (MM8)8 | 88 | [88] | |
| Me | Me | Me | 88e | [88] |
e 8.8 eeeee ee 88 eee eeee eeee eeeeeee ee eee eeeee.
Mee eeeeeeeee ee M,M- eee M,M-eeeeee-8,8-eeeee eeeeeee eeeeeeeeeeeeeeeeee ee eeee eeeeeeeeeeeeeeeee 88 (Meeeee 88).[88] Mee eeeeeeeeeeeeee eeeeee ee eee eeeeeeeeeeeeee ee ee eeeeeeeee eeee e eeeeeeeee eeeeeeeeeeeee eeeeeeeee.
Meeeee 88 Meeeeeeeeeeeee (8 + 8) Meeeeeeeeeeee ee Meeeee eeee e Meeeeeee[88]
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Meeeee 88 Meeeee Meeeeeeeee ee e β-Meeeee-Meeeeeeeeee Meeeee[88]
Meeeeeeeeeee Meeeeeeee
Meeeeeeeeeeee-8-eeee 88; Meeeeee Meeeeeeee:[88]
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References
| [75] | Meeeee, M.; Meeeee, M.; Meeeee, M.; Meeeeeee, M., M. Me. Meee. Mee., (8888) 888, 88 888. |
| [76] | Meeeee, M.; Meeeee, M.; Meeeeeee, M., Meeeeeeeeeeeeee, (8888) 88, 8888. |
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