Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA.
J Am Chem Soc. 2012 Aug 29;134(34):13978-81. doi: 10.1021/ja306902j. Epub 2012 Aug 20.
Unprotected dibenzo-7λ(3)-phosphanorbornadiene derivatives RPA (A = C(14)H(10) or anthracene; R = (t)Bu, dbabh = NA, HMDS = (Me(3)Si)(2)N, (i)Pr(2)N) are synthesized by treatment of the corresponding phosphorus dichloride RPCl(2) with MgA·3THF, in cold THF (~20% to 30% isolated yields). Anthracene and the corresponding cyclic phosphane (RP)(n) form as coproducts. Characteristic NMR features of the RPA derivatives include a doublet near 4 ppm in their (1)H NMR spectra and a triplet peak in the 175-212 ppm region of the (31)P NMR spectrum ((2)J(PH) ~14 Hz). The X-ray structures of the AN-PA and (HMDS)PA derivatives are discussed. Thermolysis of RPA benzene-d(6) solutions leads to anthracene extrusion. This process has a unimolecular kinetic profile for the (i)Pr(2)NPA derivative. The 7-phosphanorbornene anti-(i)Pr(2)NP(C(6)H(8)) could be synthesized (70% isolated yield) by thermolysis of (i)Pr(2)NPA in 1,3-cyclohexadiene.
未保护的二苯并-7λ(3)-膦杂环戊二烯衍生物 RPA（A = C(14)H(10) 或蒽；R = (t)Bu、dbabh = NA、HMDS = (Me(3)Si)(2)N、(i)Pr(2)N）是通过用 MgA·3THF 处理相应的磷二氯化物 RPCl(2)合成的，在冷 THF 中（20%至 30%的分离产率）。蒽和相应的环状膦烷（RP）(n)作为副产物形成。RPA 衍生物的特征 NMR 特征包括其（1）H NMR 谱中接近 4 ppm 的双峰和（31）P NMR 谱中在 175-212 ppm 区域的三重峰（(2)J(PH)14 Hz）。讨论了 AN-PA 和 (HMDS)PA 衍生物的 X 射线结构。RPA 苯-d(6)溶液的热解导致蒽的挤出。对于 (i)Pr(2)NPA 衍生物，该过程具有单分子动力学特征。通过在 1,3-环戊二烯中热解 (i)Pr(2)NPA 可以合成 7-磷杂环戊二烯反式-(i)Pr(2)NP(C(6)H(8))（70%的分离产率）。
