Isolable Phosphaalkenes Bearing 2,4,6-Trimethoxyphenyl and 2,6-Bis(trifluoromethyl)phenyl as P-Substituents

Abstract

The multistep synthesis and characterization of new PC analogues of olefins from readily available starting materials is reported. Specifically, the phosphaalkenes TMOP–PCPh2 (1a: TMOP = 2,4,6-trimethoxyphenyl) and ArF–PCPh2 [1b: ArF = 2,6-bis­(trifluoromethyl)­phenyl] have been prepared, isolated, and characterized. In addition, synthetically challenging intermediates, such as the corresponding pyrophoric primary phosphines and bis­(trimethylsilyl)­phosphines, have been isolated and characterized. The title compounds, TMOP–PCPh2 (1a) and ArF–PCPh2 (1b), along with TMOP–PH2 (3a) have been characterized by X-ray crystallography. Importantly, the successful synthesis and isolation of phosphaalkenes 1a and 1b provides a foundation for future investigations of their polymerization, by analogy to the known polymerization of Mes–PCPh2.

Radical Hydrophosphination Initiated by Triamidoamine-Supported Titanium Despite Insertion into the Ti–P Bond

“…The geometry of the structure indicates that the isocyanide reacted with the titanium phosphido via a 1,1-insertion followed by a subsequent rearrangement. The phosphaalkene bond, P1-C1 = 1.717( 22) Å is consistent with, if not slightly longer than, published phosphaalkenes, 22 and similar to the isostructural zirconium compounds. 23 The short C1-N1 bond length of 1.385 Å as well as the near-planarity of the Ti1-N1-C1-P1 system, as shown by dihedral angle of -168.54°, indicates significant conjugation.…”

Photo-Initiated Radical Hydrophosphination at Titanium Compounds Capable of Ti–P Insertion

“…The geometry of the structure indicates that the isocyanide reacted with the titanium phosphido via a 1,1-insertion followed by a subsequent rearrangement. The phosphaalkene bond, P1–C1 = 1.717(22) Å, is consistent with, if not slightly longer than, published phosphaalkenes and similar to the isostructural zirconium compounds . The short C1–N1 bond length of 1.385 Å as well as the near-planarity of the Ti1–N1–C1–P1 system, as shown by dihedral angle of −168.54°, indicates significant conjugation.…”

Primary Phosphines and Phosphine Oxides with a Stereogenic Carbon Center Adjacent to the Phosphorus Atom: Synthesis and Anti-Markovnikov Radical Addition to Alkenes

“…Organophosphorus compounds, and particularly those with three or four substituents on the phosphorus atom, i.e., tertiary phosphines, phosphine oxides, and their isologues, are of great importance in organic synthesis and medicinal chemistry [1][2][3]. The synthesis and reactions of primary phosphines [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18] and phosphine oxides [19][20][21] which contain two phosphorus-hydrogen (P-H) bonds have received increasing attention because these highly reactive bonds undergo various types of phosphorus-carbon (P-C) bond-forming reactions. Their highly efficient addition reactions to alkenes have been achieved with transition metal catalysts [22][23][24].…”