REACTION OF WITTIG REAGENTS AND PHOSPHACUMULENES WITH 1-(DIPHENYLMETHYLENE)-2(1H)- AND 4- (DIPHENYLMETHYLENE)-1(4H)-NAPHTHALENONES

Abstract

Depending upon the type of Wittig reagents, naphthalenone 1 reacts with reagents 3a and 3b to give adducts 4 and 5 respectively. Reaction of 1 with phosphacumulene 6 gives the phosphorane 7. On the other hand, naphthalenone 2 reacts with 3a and 3b to give adducts 8 and 9. The identity of the new compounds is established from analytical and spectroscopic evidences.

The behavior of 2-substituted-1,3-diphenylpropane-1,3-tione toward organophosphorus reagents

“…When 1,3-diphenyl-2-(phenylimino)-1,3-propanedione (1b) was treated with one equivalent of carbethoxymethylenetriphenylphosphorane (2a) in tetrahydrofuran at reflux temperature for 6 hours, adduct 6a and triphenylphosphine oxide were isolated in good yields (Scheme 4). The IR spectrum of 13 C NMR spectra, and molecular weight determination (MS) were in good agreement with structure 7a (Experimental section).…”

“…Transfer of a proton from the ␣-to the c-carbon atom leads to the formation of the new phosphonium ylides 4a-c (Scheme 2) [12,13].…”

“…Compatible analytical and spectral data (IR, 1 H, 13 C NMR, and MS) have been recorded for the new products.…”

“…The structures of 5b,c are deduced from their analysis, IR, 1 H NMR, 13 C NMR, and mass spectral data (c.f. Experimental section).…”

“…Triphenylphosphine oxide (TPPO) was also isolated and identified in each case. Compatible analytical and spectral data (IR, 1 H, 13 C NMR and MS) were obtained for the new products (cf. Experimental section).…”