165329-31-7Relevant academic research and scientific papers
Synthesis of a novel exceedingly strong nonionic superbase
D'Sa, Bosco A.,Verkade, John G.
, p. 301 - 312 (1997)
The synthesis of a novel superbase P(HNCH2CH2)(i-PrNCH2CH2) 2N, 2a, is discussed. The conditions for the preparation and purification of H2NCH2CH2N(CH2CH 2N-i-Pr)2. 4a, starting from commercially available (H2NCH2CH2)3N (tren) were optimized. The existence of the novel zwitterion HP(N-CH2CH2)(i-PrNCH2CH 2)2N+, 2b, was substantiated by NMR spectroscopy. The Superbase 2a crystallizes from its melt when cooled slowly to -4 °C, and then remains as a solid at room temperature for several days. Hence it can be handled as a liquid or as a solid.
Synthesis of new proazaphosphatranes and their application in organic synthesis
Kisanga, Philip B.,Verkade, John G.
, p. 467 - 475 (2007/10/03)
We report herein the synthesis of the new proazaphosphatrane strong bases P(RNCH2CH2)3N (R=Me3CCH2, Me2CHCH2) and P(HNCH2CH2)2NCH2CH2 N-i-Pr (1g). The new azaphosphatranes [HP(RNCH2CH2)3N]Cl (R=Me3CCH2, Me2CHCH2) have P-Nax distances of 2.047 and 1.958 ?, respectively. We also report the synthesis of the tetramine precursor proazaphosphatrane 1g [namely, (H2NCH2CH2) 2NCH2CH2NH-i-Pr] in 41% yield and the use of a complexation-extraction technique to separate it from a mixture containing the di- and tri-isopropyl substituted analogs. Using a 31P NMR technique, we report the pKa value for 1gH+ (34.49). The catalytic properties of three bases P(RNCH2CH2)3N (R=i-Pr, Piv, i-Bu) are compared in the synthesis of several β-hydroxy nitriles, β-nitroalkanols, α,β-unsaturated esters and for the Michael addition of allyl alcohol to α,β-unsaturated ketones.
