雙鉻多重鍵錯合物的合成與鑑定：從四重鍵到五重鍵

Syntheses and Characterizations of Multiply-Bonded Dichromium Complexes: From Quadruple to Quintuple Bond

許家瑋(Chia-Wei Hsu)

指導教授 ： 蔡易州

國立清華大學/理學院/化學系/碩士(2008年)

摘要

在本篇論文中，我們發表了合成雙鉻多重鍵錯合物的新方法。我們還原Cr2(u-Cl)2[(2,6-Me2C6H3)NCHN(2,6-Me2C6H3)]2(THF)2 (1)進而得到了Cr2[(2,6-Me2C6H3)NCHN(2,6-Me2C6H3)]2 (2)和 Cr2[(2,6-Me2C6H3)NCHN(2,6-Me2C6H3)]3 (3)。我們進一步以KC8來還原3，得到了[K(cryptand [2.2.2])]{Cr2[(2,6-Me2C6H3)NCHN(2,6-Me2C6H3)]3} (4) (鉻-鉻鍵長， 1.7397(9) Å)。錯合物2、3、4均以核磁共振光譜學、元素分析儀以及X光單晶繞射進行鑑定。錯合物2和4為逆磁性的錯合物並具有鉻-鉻五重鍵的性質。另一方面，我們也合成出一系列雙鉻五重鍵錯合物Cr2[ArNCRNAr]2 (Ar = 2,4,6-Me3C6H2, R = H 8; Ar = 2,6-Et2C6H3, R = H 10; Ar = 2,6-i-Pr2C6H3, R = H 12; Ar = 2,6-i-Pr2C6H3, R = CH3 14)，鉻-鉻鍵長為1.7395(7)-1.812(2) Å。錯合物8，10，12，14均以核磁共振光譜學、元素分析儀以及X光單晶繞射進行鑑定。簡而言之，我們成功地合成出對稱性為D3h和D2h的雙鉻五重鍵錯合物。另一方面，我們合成出了非平行平面雙鉻四重鍵錯合物Cr2{u-[(2-ClC6H4)NCH(tBu)N(2-ClC6H4)]Li}2{u-[(2-ClC6H4)NCH(tBu)N(2-ClC6H4)]} 16。

關鍵字

雙鉻多重鍵錯合物 ； 四重鍵 ； 五重鍵

並列摘要

In this thesis, we report the syntheses and characterizations of multiply bonded dichromium complexes. Upon reduction of Cr2(□-Cl)2[(2,6-Me2C6H3)NCHN(2,6-Me2C6H3)]2(THF)2 (1) with KC8, two quintuply-bonded dinuclear chromium complexes Cr2[(2,6-Me2C6H3)NCHN(2,6-Me2C6H3)]2 (2) and Cr2[(2,6-Me2C6H3)NCHN(2,6-Me2C6H3)]3 (3) were isolated. Subsequent reduction of 3 with KC8 in the presence of cryptand-[2.2.2] led to the formation of a quintuply-bonded Cr(I)2 compound [K(cryptand [2.2.2])]{Cr2[(2,6-Me2C6H3)NCHN(2,6-Me2C6H3)]3} (4) (Cr-Cr, 1.7397(9) Å) . Complexes 2, 3, 4 have been characterized by NMR, elemental analysis and X-ray diffraction. Complexes 2 and 4 are diamagnetic and they both feature a Cr-Cr quintuple bond. Furthermore, we also synthesized a family of Cr2[ArNCRNAr]2 (Ar = 2,4,6-Me3C6H2, R = H 8; Ar = 2,6-Et2C6H3, R = H 10; Ar = 2,6-i-Pr2C6H3, R = H 12; Ar = 2,6-i-Pr2C6H3, R = CH3 14), which all display a Cr-Cr quintuple bond with Cr-Cr bond lengths in the range of 1.7395(7)-1.812(2) Å. Complexes 8, 10, 12, 14 have been characterized by NMR, elemental analysis and X-ray diffraction. In conclusion, we successfully synthesized two types of quintuply-bonded Cr-Cr complexes, the D3h symmetry complex (4) and D2h symmetry complexes (2, 8, 10, 12, 14). In addition, we isolated an unusual quadruply-bonded Cr(II)2 complex , Cr2{u-[(2-ClC6H4)NCH(tBu)N(2-ClC6H4)]Li}2{u-[(2-ClC6H4)NCH(tBu)N(2-ClC6H4)]} (16) with a nonparallel square planes of each Cr.

並列關鍵字

Multiply-Bonded Dichromium Complexes ； Quadruple Bond ； Quintuple Bond

參考文獻

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