4-methoxyphenyl phosphonium

The present preparation illustrates a general and convenient method for the fnms-iodopropenylation of an alkyl halide.4 The iodopropenyl-ated material is not usually stable but is a useful synthetic intermediate. For example, it forms a stable crystalline triphenylphosphonium salt for use in the Wittig reaction, and under Kornblum reaction conditions (DMS0-NaHC03, 130°, 3 minutes) it gives an (E)-a,/9-unsaturated aldehyde.4 In addition to the phosphonium salt described in Note 15, the following have been prepared (4-p-methoxyphenyl-2-butenyl)-triphenylphosphonium iodide [Phosphonium, [4-(4-methoxyphenyl)-2-butenyl]triphenyl-, iodide], m.p. 123-127° (2-octenyl)triphenyl-phosphonium iodide [Phosphonium, 2-octenyltriphenyl-, iodide], m.p. 98° and (2-octadecenyl)triphenylphosphonium iodide [Phosphonium, 2-octadecenyltriphenyl-, iodide], m.p. 50°. 

Phenylurethanes. 58, 10 Phosgene, 57, 46 Phosphine, diphenyl-, 56, 45 Phosphine-nickcl catalyst, 58, 129 PHOSPHINE-NICKEL CATALYZED COMPLEX CROSS-COUPLING OF GRIG-NARD REAGENTS WITH ARYL AND ALKENYL HALIDES, 58, 127 Phosphine, phenyl-, bis(3-dimethylamino-piopyl)-, 55, 128 Phosphine, triphenyl-, 56, 81 Phosphonium, 14-(4-methoxyphenyl)-2-butenyl] triphenyl-, iodide, 56, 81 Phosphonium, 2-octadecenyltriphenyl-, iodide, 56, 81... 

Phosphine, diphenyl- [829-85-6], 45 Phosphine, triphenyl- [603-35-0], 81 Phosphonium, [4- 4-methoxyphenyl)-2-butenyl) triphenyl-, iodide [57620-96-91,81... 

We reacted the phosphonium salts XXVIa—XXVIc with carbonyl compounds under varied experimental conditions. It was shown that when the oleHnation was carried out in absolute ether with lithium diisopropylamide as deprotonation agent — in accordance with the reaction under discussion — the phosphonium salt XXVIa and benzaldehyde formed the Schiff base of the cinnamaldehyde XXVII in 77% yield. In comparison the yield is reduced when, in place of the p-N,N-dimethylamino-phenyl residue in XXVIa, the p-methoxyphenyl residue (XXVIb) is introduced. Using approximately the same reaction conditions, it falls to 65% of XXVIII and still further to 36% of XXIX when the cyclohexyl residue is present in phosphonium salt (XXVIc). The reaction of the phosphonium salt XXVIa with cinnamaldehyde produced only 20% of the expected Schiff base. 

Triphenylphosphin-2-formyl-propen-1 -yl-methylen T riphenyl-3-formyl-buten-2-yl-l -phosphonium-chlorid 1,9-Bis-[4-methoxyphenyl]-nona-tetraen-(l, 3,5,7)carbonium-perchlorat... 

The pyrolysis of aryl propiolates 170 as a route to cycloheptafuranones 171 has been extended to highly substituted examples with three to five methyl or ethyl substituents (Scheme 34 2000HCA1022). The formation of benzofurans upon FVP of stabilized phosphonium ylides carrying an orf/ o-methoxyphenyl group, previously reported for ylides with C=PPh3 and C=0 functions interchanged, also occurs with the isomeric compounds... 

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