33535-75-0Relevant academic research and scientific papers
SYNTHESIS, STRUCTURE AND REACTIVITY OF BIS(N-ARYL-IMINOPHOSPHORANYL)METHANES. X-RAY CRYSTAL STRUCTURES OF (4-CH3-C6H4-N=PPh2)2CH2 AND (4-NO2-C6H4-N=PMe2)2CH2
Imhoff, P.,van Asselt, R.,Elsevier, C. J.,Vrieze, K.,Goubitz, K.,et al.
, p. 401 - 415 (2007/10/02)
The synthesis of novel bis(N-aryl-imino-phosphoranyl)methanes of the type CH2(PR2=N-Ar)2 has been accomplished by reaction of methylene-bisphosphines with arylazides.These compounds have been fully characterized by 1H, 31P and 13C NMR, IR spectroscopy, Field Desorption Mass Spectroscopy (=FDMS) and elemental analysis.Variable temperature NMR experiments and single crystal X-ray structure determination of CH2(PPh2=N-C6H4-CH3-4)2 (1a) and CH2(PMe2=N-C6H4-NO2-4)2 (1f) reveal that bis(N-aryl-imino-phosphoranyl)methane occurs as tautomer 1.Crystals of 1a are orthorhombic, space group Pcab, with a=26.602(2), b=20.521(1), c=11.8859(7) A and V=6488.5(7) A3 (Z=8, R=0.045 and RW=0.066).The crystals of 1f are monoclinic, space group C/2c, with a=20.153(4), b=5.952(1), c=16.930(5) A, β=106.24(3) deg and V=1949.6(6) A3 (Z=4, molecular symmetry C2, R=0.051 and RW=0.079).Both molecules consist of 2 iminophosphoranyl units bridged by a methylene group.The P=N bond distances of 1.568(2) and 1.566(2) A for 1a and 1.580(4) A for 1f represent normal values for iminophosphoranyl compounds.The N-C bond lengths of 1.386(2) and 1.390(2) A (1a) or 1.372(5) A for 1f indicate that some electron delocalization over the N-aryl moiety takes place.In 1a the electron delocalization takes place separately in each iminophosphoranyl entity, while in 1f electron delocalization occurs only in the N-aryl-NO2 moiety.Compound 1a is easily deprotonated using lithium-diisopropylamide or NaH and shows typical iminophosphoranyl chemistry, since with CO2 an aza-Wittig reaction has been found and with HX (X=Cl, Br) protonation of both imide nitrogen atoms has been observed.
