A strategy for copper-catalyzed and biphosphine ligand controlled boracarboxylation of 1,3-dienes and CO2 with 3,4-selectivity was developed. The CuCl coupled with DPPF (1,1′-bis(diphenylphosphino)ferrocene) was assigned to be the best catalyst, with 84% yield and exclusive 3,4-selectivity. The ligand effect on both catalytic activity and regioselectivity of boracarboxylation was disclosed, which is rarely reported in any copper catalyzed boracarboxylation. The borocupration process is revealed to be a vital step for the biphosphine participated boracarboxylation of 1,3-dienes with CO2. The minimal substrate distortion occurring in 3,4-borocupration favors the 3,4-regioselectivity of boracarboxylation. The “pocket” confinement and suitable βn (92°–106°) of bisphosphine ligands are demonstrated to be in favour of the interaction between LCu-Bpin complex (the catalytic precursor) and 1,3-diene substrate to decrease their interaction energy ∆Eint(ζ) in 3,4-borocupration, thus promoting the 3,4-boracarboxylation.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |