%0 Generic %A Becker, Gerd %A Brombach, Heike %A Horner, Stephen T. %A Niecke, Edgar %A Schwarz, Wolfgang %A Streubel, Rainer %A Würthwein, Ernst-Ulrich %D 2005 %T Synthesis and Structure of K+[iPrNCP]-, a 1-Aza-3λ3-phospha-3-allenide %U https://acs.figshare.com/articles/dataset/Synthesis_and_Structure_of_K_sup_sup_i_sup_i_sup_i_sup_sup_PrN_C_P_sup_sup_a_1_Aza_3_sup_3_sup_phospha_3_allenide_sup_sup_/3373936 %R 10.1021/ic048162+.s001 %2 https://acs.figshare.com/ndownloader/files/5217412 %K λ 3 %K quantum chemical calculations %K potassium %K anion %K phosphaalkyne 1 %X 2-Isopropyl(trimethylsilyl)amino-1λ3-phosphaalkyne 1 reacts with potassium tert-butoxide to form potassium 1-isopropyl-1-aza-3λ3-phospha-3-allenide (2). This compound was structurally characterized as the corresponding 18-crown-6 ether complex 3. The molecular structure of 1 was also determined in order to compare the bonding situation in the anion and the neutral λ3-phosphaalkyne. Compound 3 contains a nitrogen−carbon−phosphorus group for which the parameters were shown by X-ray structural analysis and quantum chemical calculations to lie between the extrema N−C⋮P and NCP, suggesting reactivity typical of an ambident anion. This is indeed the case, as subsequent reaction of 2 with chlorotrimethylsilane at nitrogen regenerates the λ3-phosphaalkyne 1; with chlorotriphenylsilane the new derivative 4 is formed. In contrast, chlorotrimethylstannane reacts at phosphorus, giving the 1-aza-3λ3-phosphaallene isopropyliminomethylidene(trimethylstannyl)phosphane 5. %I ACS Publications