| Abstract: | Contributions to the Chemistry of Phosphorus. 123. Synthesis and Properties of the Diphosphagermiranes (t-BuP)2GePh2 and (t-BuP)2GeEt2 The first three-membered P2Ge heterocycles, 1,2-di-tert-butyl-3, 3-diphenyl-1, 2, 3-diphosphagermirane, (t-BuP)2GePh2 (1) , and 1, 2-di-tert-butyl-3, 3-diethyl-1, 2, 3-diphosphagermirane, (t-BuP)2GeEt2 (2) , were synthesized by 2+1] cyclocondensation reactions of K(t-Bu)P—P(t-Bu)K with diphenylgermanium dichloride and diethylgermanium dichloride, respectively. The four-, five-, and six-membered cyclogermaphosphanes (t-BuP)2(GePh2)2 (3) , (t-BuP)3GeR2 ( 6 R = Ph; 7 R = Et), (t-BuP)4GePh2 (5) and (t-BuP)4(GePh2)2 (4) as well as (t-BuP)4 are formed as by-products. The diphosphagermiranes 1 and 2 could be isolated in 93 and 100% purity, respectively, and were unambiguously characterized as compounds with a cyclic P2Ge skeleton. The 31P-NMR parameters of the cyclogermaphosphanes 3—7 are reported. |
