Dppm-derived phosphonium salts and ylides as ligand precursors for s-block organometallics
作者:Jens Langer、Sascha Meyer、Feyza Dündar、Björn Schowtka、Helmar Görls、Matthias Westerhausen
DOI:10.3998/ark.5550190.0013.316
日期:——
(dppm) and haloalkanes R-X yields the corresponding phosphonium salts (Ph2PCH2PPh2R)X (1a: R = Me, X = I; 1b: R = Et, X = Br; 1c: R = iPr, X = I; 1d: R = CH2Mes, X = Br; 1e: R = tBu, X = Br). In case of the synthesis of 1e, (Ph2MePH)Br (3) was identified as a by-product. Deprotonation of 1 by KOtBu offers access to the corresponding phosphonium ylides (Ph2PCHPPh2R) (2a: R = Me; 2b: R = Et; 2c: R = iPr;
1,1-双(二苯基膦基)甲烷 (dppm) 和卤代烷烃 RX 的加成反应产生相应的鏻盐 (Ph2PCH2PPh2R)X (1a: R = Me, X = I; 1b: R = Et, X = Br; 1c :R = iPr,X = I;1d:R = CH2Mes,X = Br;1e:R = tBu,X = Br)。在合成 1e 的情况下,(Ph2MePH)Br (3) 被确定为副产物。KOtBu 对 1 的去质子化以良好的产率获得相应的鏻叶立德 (Ph2PCHPPh2R)(2a:R = Me;2b:R = Et;2c:R = iPr;2d:R = CH2Mes)。使用正丁基锂对 2a 进行进一步去质子化可以分离锂络合物 (Li(Ph2PCHPPh2CH2))n (4) 及其单体 tmeda 加合物 ((tmeda)Li(Ph2PCHPPh2CH2)) (4a)。所有化合物均通过 NMR 测量和