Table 5.
Effect of Brønsted base on cycloisomerization with different catalysts
![]() | |||
|---|---|---|---|
| entry | cat (mol%) | % conversion of 39ba (no base) | % conversion of 39ba (with TTBPb) |
| 1 | TfOH (10) | 100c | <1d |
| 2 | Cu(OTf)2 (5) | 100e | 100e |
| 3 | PdCl2(MeCN)2 (5) | 100e | 100e |
| 4 | AgOTf (5) | 100e | 100e |
| 5 | PtCl2 (5) | 100f | 100f |
| 6 | AuCl3 (5) | 100e | 100e |
based on GC analysis. Yields comparable to that reported in Table 2.
1.5 eq (vs catalyst) 2,4,6-tri-tertbutylpyrimidine (TTBP) added.
reaction complete after 6 hours.
reaction checked after 24 hours.
reaction complete within 30 minutes.
reaction complete within 3.5 hours.
