Catalytic reduction of dinitrogen to ammonia at a single molybdenum center
Catalytic reduction of dinitrogen to ammonia at a single molybdenum center
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DOI：
10.1126/science.1085326
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发表时间：
2003-07-04
期刊：
影响因子：
56.9
通讯作者：
Schrock, RR
中科院分区：
文献类型：
--
作者：
Yandulov, DV;Schrock, RR
在室温和1个大气压下，用钼催化剂将二氮（N-2）还原成氨，所述钼催化剂含有在庚烷中的四齿[HIPTN 3 N]（3-）三酰胺基胺配体{例如[HIPTN 3 N]Mo（N-2），其中[HIPTN 3 N]（3-）是[{3，5-（2，4，6-i-Pr 3C 6 H2）（2）C6 H3 NCH 2CH 2}（3）N]（3-）}。缓慢加入质子源[{2，6-lutidinium}{BAr '（4）}，其中Ar'是3，5-（CF 3）（2）C6 H3]和还原剂（十甲基二茂铬）对于实现高效率（在四次转换中类似于66%）是关键的。大量的X射线研究，沿着分离和表征了六种在非催化条件下催化反应中的中间体，表明N-2在空间保护的单一钼中心被还原，该中心从Mo（III）到Mo（VI）状态循环。
Dinitrogen (N-2) was reduced to ammonia at room temperature and 1 atmosphere with molybdenum catalysts that contain tetradentate [HIPTN3N](3-) triamidoamine ligands {such as [HIPTN3N]Mo(N-2), where [HIPTN3N](3-) is[{3,5-(2,4,6-i-Pr3C6H2)(2)C6H3NCH2CH2}(3)N](3-)} in heptane. Slow addition of the proton source [{2,6-lutidinium}{BAr'(4)}, where Ar' is 3,5-(CF3)(2)C6H3] and reductant (decamethyl chromocene) was critical for achieving high efficiency (similar to66% in four turnovers). Numerous x-ray studies, along with isolation and characterization of six proposed intermediates in the catalytic reaction under noncatalytic conditions, suggest that N-2 was reduced at a sterically protected, single molybdenum center that cycled from Mo(III) through Mo(VI) states.