Deoxygenation of Mono-oxo Bis(dithiolene) Mo and W Complexes by Protonation

作者:Seo Junhyeok; Williard Paul G; Kim Eunsuk*
来源:Inorganic Chemistry, 2013, 52(15): 8706-8712.
DOI:10.1021/ic4008747

摘要

Protonation-assisted deoxygenation of a monooxo molybdenum center has been observed in many oxotransferases when the enzyme removes an oxo group to regenerate a substrate binding site. Such a reaction is reported here with discrete synthetic mono-oxo bis(dithiolene) molybdenum and tungsten complexes, the chemistry of which had been rarely studied because of the instability of the resulting deoxygenated products. An addition of tosylic acid to an acetonitrile solution of [(MoO)-O-IV(S2C2Ph2)(2)](2-) (1) and [(WO)-O-IV(S2C2Ph2)(2)](2-) (2) results in the loss of oxide with a concomitant formation of novel deoxygenated complexes, [M(MeCN)(2)(S2C2Ph2)(2)] (M = Mo (3), W (4)), that have been isolated and characterized. Whereas protonation of 1 exclusively produces 3, two different reaction products can be generated from 2; an oxidized product, [WO(S2C2Ph2)(2)](-), is produced with 1 equiv of acid while a deoxygenated product, [W(MeCN)(2)(S2C2Ph2)(2)] (4), is generated with an excess amount of proton. Alternatively, complexes 3 and 4 can be obtained from photolysis of [Mo(CO)(2)(S2C2Ph2)(2)] (5) and [W(CO)(2)(S2C2Ph2)(2)] (6) in acetonitrile. A di- and a monosubstituted adducts of 3, [Mo(CO)(2)(S2C2Ph2)(2)] (5) and [Mo(PPh3)(MeCN)(S2C2Ph2)(2)] (7) are also reported.

  • 出版日期2013-8-5