Reaktive E=C (p-p)π-System e, XXX. Darstellung und Reaktivität der Fluorphosphaalkene Me2N -P = CF2 und Me2N -P = C(F)CF3 / Reactive E = C (p -p )π-Systems, XXX. Synthesis and Reactivity of the Fluorophosphaalkenes Me2N - P = CF2 and Me2N - P = C(F)CF3
Zeitschrift für Naturforschung. B, A journal of chemical sciences
Gas phase thermolyses of the stannylphosphanes Me3SnP(CF3)NMe2(3) and Me3SnP(C2F5)NMe2 (4) yield the novel amino substituted fluorophosphaalkenes Me2N -P = CF2 (1) (10 to 15% yield) and Me2N - P = C(F)CF3 (2) (90% yield), respectively. In contrast to other derivatives, 1 cannot be prepared by the reaction of the secondary phosphane Me2NP(H)CF3 (9) with secondary or tertiary amines or KOH. 1 and 2 are labile compounds which undergo quick oligomerization above 0 °C to (Me2NPCF2)n and
... )n and (Me2NPCFCF3)n, respectively. By thermal degradation of (Me2NPCF2)n at 500 to 600 °C the trans- 1 ,3-diphosphetane (Me2NPCF2)2 (11) is formed in high yield. Reaction of 2 with cyclopentadiene leads to the corresponding [2+4] cycloadduct 2-dimethylamino-3-fluoro-3-(trifluoromethyl)-2-phosphabicyclo [2.2.1]-hept-5-ene (12). New compounds were characterized by spectroscopic methods (NMR, MS).