Synthesis and Rearrangement of P-Nitroxyl-Substituted P(III) and P(V) Phosphanes: A Combined Experimental and Theoretical Case Study.
Low-temperature generation of P-nitroxyl phosphane 2 (Ph2 POTEMP), which was obtained by the reaction of Ph2 PH (1) with two equivalents of TEMPO, is presented. Upon warming, phosphane 2 decomposed to give P-nitroxyl phosphane P-oxide 3 (Ph2 P(O)OTEMP) as one of the final products. This facile synthetic protocol also enabled access to P-sulfide and P-borane derivatives 7 and 13, respectively, by using Ph2 P(S)H (6) or Ph2 P(BH3 )H (11) and TEMPO. Phosphane sulfide 7 revealed a rearrangement to phosphane oxide 8 (Ph2 P(O)STEMP) in CDCl3 at ambient temperature, whereas in THF, thermal decomposition of sulfide 7 yielded salt 10 ([TEMP-H2 ][Ph2 P(S)O]). As well as EPR and detailed NMR kinetic studies, indepth theoretical studies provided an insight into the reaction pathways and spin-density distributions of the reactive intermediates.
Institut für Anorganische Chemie, Rheinische Friedrich-Wilhelms-Universität Bonn, Gerhard-Domagk-Str. 1, 53121, Bonn, Germany.
Tobias
T
Heurich
Mulliken Center for Theoretical Chemistry, Rheinische Friedrich-Wilhelms-Universität Bonn, Beringstr. 4, 53115, Bonn, Germany.
Zheng-Wang
ZW
Qu
Institut für Anorganische Chemie, Rheinische Friedrich-Wilhelms-Universität Bonn, Gerhard-Domagk-Str. 1, 53121, Bonn, Germany.
Senada
S
Nožinović
Institut für Anorganische Chemie, Rheinische Friedrich-Wilhelms-Universität Bonn, Gerhard-Domagk-Str. 1, 53121, Bonn, Germany.
Gregor
G
Schnakenburg
Institut für Physikalische und Theoretische Chemie, Rheinische Friedrich-Wilhelms-Universität Bonn, Wegelerstr. 12, 53115, Bonn, Germany.
Hideto
H
Matsuoka
Mulliken Center for Theoretical Chemistry, Rheinische Friedrich-Wilhelms-Universität Bonn, Beringstr. 4, 53115, Bonn, Germany. grimme@thch.uni-bonn.de.
Stefan
S
Grimme
Institut für Physikalische und Theoretische Chemie, Rheinische Friedrich-Wilhelms-Universität Bonn, Wegelerstr. 12, 53115, Bonn, Germany. schiemann@pc.uni-bonn.de.
Olav
O
Schiemann
Institut für Anorganische Chemie, Rheinische Friedrich-Wilhelms-Universität Bonn, Gerhard-Domagk-Str. 1, 53121, Bonn, Germany. r.streubel@uni-bonn.de.
Rainer
R
Streubel
EPR spectroscopy; TEMPO; density functional calculations; nitroxyl; phosphanes