Table 2.
Solvent dependant intramolecular [2+2] photocycloadditions
| entry | enone | products | solvent/yield/ratio | |
|---|---|---|---|---|
| (1) | ![]() |
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CH2Cl2 80% 14a/14b (1:6) acetone/H2O 60% 14a/14b (>20:1) |
| (2) | ![]() |
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CH2Cl2 89% (81% conv.) MeOH 60% (87% conv.) |
|
| (3) | ![]() |
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CH2Cl2 72% 18a/18b (1:4) acetone/H2O 74% 18a/18b (6:1) |
| (4) | ![]() |
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CH2Cl2 47% 19a/19b (>1:20) acetone/H2O 38% 19a/19b (>20:1) |
| (5) | ![]() |
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CH2Cl2 21% 20a/20b(1:10) acetone/H2O 40% 20a/20b (16:1) |
All reactions: hv, Pyrex filter, 3mM in solvent.













