Maaninen T, Chivers T, Laitinen R, Schatte G, Nissinen M
Department of Chemistry, University of Calgary, 2500 University Drive, N.W., Calgary, Alberta, Canada T2N 1N4.
Inorg Chem. 2000 Nov 13;39(23):5341-7. doi: 10.1021/ic000598b.
The reaction of SeCl2 with tert-butylamine in various molar ratios in THF at -78 degrees C has been investigated by 77Se NMR spectroscopy. In addition to the known Se-N heterocycles Se6(NtBu)2 (1) and Se9(NtBu)6 (2), the acyclic imidoselenium(II) dichlorides ClSe[N(tBu)Se]nCl (4, n = 1; 5, n = 2) and two new cyclic selenium imides [Se3(NtBu)2]n (3, n = 1 or 2) and Se3(NtBu)3 (6) have been isolated and identified. An X-ray analysis shows that 6 is a six-membered ring in a chair conformation with magnitude of d(Se-N) = 1.833 A. Crystal data: 6, trigonal, P3c1, a = 9.8660(3) A, c = 20.8427(7) A, V = 1757.0(1) A3, Z = 6. The 1H, 13C, and 77Se NMR data for 1-6 are reported, and some reassignments of earlier literature data for 1-3 (n = 1) are made. The decomposition of tBuN=Se=NtBu at 20 degrees C in toluene was monitored by 77Se NMR. The major products are 6 and 3. The Se(IV)-N systems tBuNSe(mu-NtBu)2E (7, E = SO2; 8, E = SeO) were prepared by the reaction of a mixture of SeCl4 and excess tBuNH2 with SO2Cl2 or SeOCl2, respectively. Compound 8 is also generated by the cycloaddition reaction of tBuNSeNtBu with tBuNSeO. Both 7 and 8 consist of slightly puckered four-membered rings. The mean terminal and bridging Se-N distances in 7 are 1.665(2) and 1.948(2) A, respectively. The corresponding values for 8 are 1.687(4) and 1.900(4) A, and d(Se=O) = 1.628(4) A. Crystal data: 7, monoclinic, P2(1)/c, a = 18.669(4) A, b = 12.329(2) A, c = 16.463(3) A, beta = 115.56(3) degrees, V = 3418.4(11) A3, Z = 4; 8, triclinic, P1, a = 6.372(1) A, b = 9.926(2) A, c = 14.034(3) A, alpha = 99.320(3) A, beta = 95.764(3) A, gamma = 103.876(3) A, V = 841.3(3) A3, Z = 2.
通过(^{77}Se)核磁共振光谱研究了(SeCl_2)与叔丁胺在四氢呋喃中于(-78^{\circ}C)以不同摩尔比进行的反应。除了已知的(Se - N)杂环(Se_6(NtBu)_2)（1）和(Se_9(NtBu)_6)（2）外，还分离并鉴定出了无环亚氨基硒（II）二氯化物(ClSe[N(tBu)Se]_nCl)（4，(n = 1)；5，(n = 2)）以及两种新的环状硒亚胺([Se_3(NtBu)_2]_n)（3，(n = 1)或2）和(Se_3(NtBu)_3)（6）。X射线分析表明，6是一个椅式构象的六元环，(d(Se - N))值为(1.833)埃。晶体数据：6，三方晶系，(P3c1)，(a = 9.8660(3))埃，(c = 20.8427(7))埃，(V = 1757.0(1))埃³，(Z = 6)。报告了1 - 6的(^1H)、(^{13}C)和(^{77}Se)核磁共振数据，并对1 - 3（(n = 1)）的早期文献数据进行了一些重新归属。通过(^{77}Se)核磁共振监测了叔丁基硒氮烯（(tBuN=Se=NtBu)）在(20^{\circ}C)甲苯中的分解。主要产物是6和3。硒（IV） - 氮体系(tBuNSe(μ - NtBu)_2E)（7，(E = SO_2)；8，(E = SeO)）分别通过(SeCl_4)与过量叔丁胺的混合物与(SO_2Cl_2)或(SeOCl_2)反应制备。化合物8也可通过叔丁基硒氮烯与叔丁基硒氧化物的环加成反应生成。7和8均由略微褶皱的四元环组成。7中末端和桥连的平均(Se - N)距离分别为(1.665(2))埃和(1.948(2))埃。8的相应值为(1.687(4))埃和(1.900(4))埃，(d(Se = O)=1.628(4))埃。晶体数据：7，单斜晶系，(P2(1)/c)，(a = 18.669(4))埃，(b = 12.329(2))埃，(c = 16.463(3))埃，(\beta = 115.56(3)^{\circ})，(V = 3418.4(11))埃³，(Z = 4)；8，三斜晶系，(P1)，(a = 6.372(1))埃，(b = 9.926(2))埃，(c = 14.034(3))埃，(\alpha = 99.320(3)^{\circ})，(\beta = 95.764(3)^{\circ})，(\gamma = 103.876(3)^{\circ})，(V = 841.3(3))埃³，(Z = 2)。
