碲二亚胺二聚体RNTe(μ-NR')(2)TeNR（R = R' = (t)Bu；R = PPh(2)NSiMe(3)，R' = (t)Bu，(t)Oct）的制备、晶体结构及异构化：碲二唑二聚体[(t)Bu(2)C(6)H(2)N(2)Te](2)的X射线结构

Preparation, Crystal Structures, and Isomerization of the Tellurium Diimide Dimers RNTe(&mgr;-NR')(2)TeNR (R = R' = (t)Bu; R = PPh(2)NSiMe(3), R' = (t)Bu, (t)Oct): X-ray Structure of the Telluradiazole Dimer [(t)Bu(2)C(6)H(2)N(2)Te](2).

作者信息

Chivers Tristram, Gao Xiaoliang, Parvez Masood

机构信息

Department of Chemistry, The University of Calgary, Calgary, Alberta, Canada T2N 1N4.

出版信息

Inorg Chem. 1996 Jan 3;35(1):9-15. doi: 10.1021/ic950154t.

DOI:10.1021/ic950154t

PMID:11666156

Abstract

The reaction of R'NHLi (R = (t)Bu, (t)Oct) with Ph(2)P(NSiMe(3))(2)Te(Cl)NPPh(2)NSiMe(3) in toluene at -78 degrees C, followed by warming to 23 degrees C, produces the tellurium diimide dimers RNTe(&mgr;-NR')(2)TeNR (2a, R' = (t)Bu, R = NPPh(2)NSiMe(3); 2b, R' = (t)Oct, R = NPPh(2)NSiMe(3)) and Ph(2)P(NHSiMe(3))(NSiMe(3)). X-ray analyses revealed that 2a and 2b have centrosymmetric structures containing a planar four-membered Te(2)N(2) ring and short exocyclic tellurium-nitrogen bond lengths (d(Te-N) = 1.900(5) and 1.897(4) or 1.905(4) Å for 2a and 2b, respectively). The exocyclic imido substituents adopt a trans arrangement with respect to the Te(2)N(2) ring. By contrast, the reaction of 2,4,6-(t)Bu(3)C(6)H(2)NHLi with Ph(2)P(NSiMe(3))(2)Te(Cl)NPPh(2)NSiMe(3) in toluene under similar conditions produces the telluradiazole ((t)Bu(2)C(6)H(2)N(2)Te)(2) (3), which exists as a weakly associated dimer in the solid state with intramolecular Te-N distances of 2.628(4) Å. The tellurium diimide dimer (t)BuNTe(&mgr;-N(t)Bu)(2)TeN(t)Bu (2c'), prepared by the reaction of TeCl(4) with (t)BuNHLi in a 1:4 molar ratio, consists of a folded Te(2)N(2) ring with exocyclic N(t)Bu groups in a cis orientation. The (1)H, (31)P, and (125)Te NMR spectra of 2a and 2b indicate that the trans isomers slowly transform into the corresponding cis isomers in solution. Crystals of 2b are triclinic, space group P&onemacr; (No. 2), with a = 13.304(3) Å, b = 16.927(3) Å, c = 13.292(5) Å, alpha = 98.94(2), beta = 109.27(2), gamma = 69.04(2) degrees, V = 2636(1) Å(3), and Z = 4. The final R and R(w) values were 0.034 and 0.033, respectively. Crystals of 2c' are orthorhombic, space group Pnma (No. 62), with a = 9.535(3) Å, b = 14.264(3) Å, c = 16.963(4) Å, V = 2307.1(9) Å(3), and Z = 4. The final R and R(w) values were 0.040 and 0.040, respectively. Crystals of 3 are monoclinic, space group P2(1)/n (No. 14), with a = 9.117(3) Å, b = 11.481(4) Å, c = 16.550(4) Å, beta = 97.76(2) degrees, V = 1716.5(8) Å(3), and Z = 4. The final R and R(w) values were 0.031 and 0.034, respectively.

摘要

R'NHLi（R = 叔丁基，叔辛基）与Ph(2)P(NSiMe(3))(2)Te(Cl)NPPh(2)NSiMe(3)在甲苯中于-78℃反应，随后升温至23℃，生成碲二亚胺二聚体RNTe(μ-NR')(2)TeNR（2a，R' = 叔丁基，R = NPPh(2)NSiMe(3)；2b，R' = 叔辛基，R = NPPh(2)NSiMe(3)）和Ph(2)P(NHSiMe(3))(NSiMe(3))。X射线分析表明，2a和2b具有中心对称结构，包含一个平面四元Te(2)N(2)环以及较短的环外碲-氮键长（2a的d(Te-N) = 1.900(5) Å，2b的d(Te-N) = 1.897(4) 或1.905(4) Å）。环外亚氨基取代基相对于Te(2)N(2)环呈反式排列。相比之下，2,4,6-叔丁基-3-苯基环己基-NHLi与Ph(2)P(NSiMe(3))(2)Te(Cl)NPPh(2)NSiMe(3)在甲苯中于类似条件下反应生成碲二唑((叔丁基)2C6H2N2Te)2（3），其在固态中以弱缔合二聚体形式存在，分子内Te-N距离为2.628(4) Å。通过TeCl(4)与叔丁基-NHLi以1:4摩尔比反应制备的碲二亚胺二聚体叔丁基-NTe(μ-N叔丁基)(2)Te-N叔丁基（2c'）由一个折叠的Te(2)N(2)环组成，环外N叔丁基基团呈顺式取向。2a和2b的1H、31P和125Te NMR谱表明，反式异构体在溶液中会缓慢转化为相应的顺式异构体。2b的晶体为三斜晶系，空间群P1̅（编号2），a = 13.304(3) Å，b = 16.927(3) Å，c = 13.292(5) Å，α = 98.94(2)，β = 109.27(2)，γ = 69.04(2)°，V = 2636(1) Å3，Z = 4。最终的R和R(w)值分别为0.034和0.033。2c'的晶体为正交晶系，空间群Pnma（编号62），a = 9.535(3) Å，b = 14.264(3) Å，c = 16.963(4) Å，V = 2307.1(9) Å3，Z = 4。最终的R和R(w)值分别为0.040和0.040。3的晶体为单斜晶系，空间群P2(1)/n（编号14），a = 9.117(3) Å，b = 11.481(4) Å，c = 16.550(4) Å，β = 97.76(2)°，V = 1716.5(8) Å3，Z = 4。最终的R和R(w)值分别为0.031和0.034。