3-Phospholene, 3-methyl-1-phenyl

Im Gegensatz zu Phosphol-Derivaten erhalt man mit 3-Methyl-l-phenyl-4,5-dihydro-phospholen und aromatischen Carbonsaure-chloriden 3-Methyl- /-phenyl-4,5-dihydro-phosphol-1 -oxid und einen aromatischen Aldehyd292. Offensichtlich wird aus der apicalen Position des intermediaren Phosphorans der Aroyl-Rest verdrangt. Die Reaktion laBt sich zur gezielten Synthese von aromatischen Aldehyden aus Acylchloriden verwenden (Alternative zur Rosenmund-Reaktion) ... 

Methyl-l-phenyl-3-phospholene, 152 Methyl phenyl sulfide, 89... 

Going one stage further phospholes present distinctive features on account of the aromatic character <1967 78 1969,77) this property is clearly reflected in the values of the coupling constants. The relevant data for 1-methyl phospholes have been published (1969>77) and are shown in 98 these are obviously contrary to the trends previously reported for 2-phospholenes in which 2/(P-CH) < 3/(PCCH). However, these are in agreement with observations on l-phenyl-2,5-dimethylphosphole (99)(1967 70) and on l-phenyl-3,4-dimethylphosphole (100) (1969,20) in the latter compound both couplings mentioned have been found to be of the same sign. 

To address this concern uretonimine-modified isocyanates with improved low-temperature properties were prepared using 4,4 -diphenylmethane diisocyanate catalyzed with 3-methyl-l-phenyl-3-phospholene-l-oxide. The formation of uretonimine was consistently higher than uretdione formation using this catalyst. The uretonimine-modified isocyanate can be stored at temperatures substantially lower than ambient temperature while still remaining liquid. In addition it is soluble in melted 4,4 -diphenylmethane diisocyanate. 

A reactor was charged with 93.80% 4,4 -diphenylmethane diisocyanate, 6.20% 2,4 -diphenylmethane diisocyanate, and 3-methyl-1 -phenyl-3-phospholene-1 -oxide (6 ppm) as catalyst and then heated for 6 hours at 110°C. Trifluoromethanesulfonic acid (50 ppm) was then added to quench the reaction. The mixture was then cooled to 50°C and the product isolated having a 29.5% isocyanate content. 

Rosthauser et al. (4) used l-methyl-3-phospholene-l-oxide to prepare and isolate oligomeric diisocyanates containing dicarbodiimides using 4,4 -diphenyl-methane diisocyanate. Diisocyanates containing dicarbodiimides were also prepared by Takahashi et al. (5) using 3-methyl-l-phenyl-2-phospholene-l-oxide as the reaction catalyst. 

The 2- and 3-phospholenes are prepared by the McCormack reaction and are good candidates as starting materials for the preparation of five-and six-membered phosphorus heterocycles [25-27]. From l-methoxy-3-methyl-2-phospholene 64 or l-methoxy-2,3-diacetoxy-3-methylphospholane 67, l-aryoxy-3-methyl-2-phospholenes 66a-c (Scheme 19), or l-aryoxy-2,3-diacetoxy-3-methylphospholane 69 (Scheme 20) with a substituted phenyl group at phosphorus, or l-aryl-3-methyl-2-phospholenes 71a-g (Scheme 21) are prepared by a substitution reaction and/or a Grignard coupling reaction [28,29]. 

Dibromo-3-methyl-l-phenylphospholane 1-oxide (125) prepared from l-phenyl-3-methyl-2-phospholene 1-oxide and bromine in the presence of... 

H)-Oxazolones were unknown until 1949 when the 2-phenyl derivative was prepared by the action of diazomethane on benzoyl isocyanate (equation 145) (49JA4059). Treatment of the phospholene (293) with acyl isocyanates (294 R = Ph, MeO or Ph2N) affords 5-acetyl-5-methyl-4(5.flr)-oxazolones (equation 146). 

Two-Step Process. A mixture composed of 100 g of 4,4 -diphenylmethane diisocyanate and 1.1 g of l-phenyl-3-methyl-l-phospholene oxide is stirred for 3 minutes at room temperature. After carbon dioxide is evolved 4.0 g of 2,4,6-tris(dimethylaminomethyl) phenol is added into the reaction mixture. The mixture generates a reaction exotherm and expands to form a foamed product. After curing at 125°C for one hour, the resultant foam is colorless and posesses low friability. 

A foam was prepared firom polymeric isocyanate (134 pbw) 3,3, 4,4 -benzophenonetetracarboxylic dianhydride (45 pbw) epoxy novolak resin (20 pbw) wetting agent (1 pbw) methanol (2.5 pbw) N,N, N -tris(dimethylaminopropyl)-s-hexahydrotriazine (2.5 pbw) triethylenediamine (2.5 pbw) and l-phenyl-3-methyl-2-phospholene 1-oxide (2.5 pbw). 

Reaction of 2,3-dimethyl-1,3-butadiene with methyl acetoacetate is carried out with PdCl2 as a catalyst in the presence of sodium phenoxide. When triphenylphos-phine is employed, a 1 2 adduct is obtained. On the other hand, the use of 3-methyl-l-phenyl-A3-phospholene (168) at 100 °C causes formation of a 1 1 adduct to give... 

Fragmentation of phosphoranes.3 3-Methyl-1 -phenyl-3-phospholene (1) reacts with diethyl peroxide to give the phosphorane (2), which fragments spontaneously at room temperature to give isoprene (3) and diethyl phenylphosphonite (4). 

For catalyzed dimerization of phenyl isocyanate to diphenylcarbodiimide, see 3-Methyl-1 -ethyl-3-phospholene-1 -oxide. 

An efficient method for preparation of aromatic and aliphatic carbodiimides involves the reaction of an Isocyanate with 3-methyl-1-phenyl-S-phospholene-1-oxide, the most readily prepared catalyst of Us type. ... 

Since the double-bond isomerization was at first unrecognized and later recognized only in the hydrolysis products, the position of the double bond in most of the compounds described in the literature must be regarded as uncertain. The only proved facts seem to be that with isoprene dichloro(phenyl)-phosphine gives the 2-phospholene derivative, that dichloro(methyl)phosphine and dibromo(phenyl)phosphine give the 3-phospholene, whereas also with 2,3-dimethylbutadiene dichloro(phenyl)phosphine gives the non-isomerized product of type (1).38,39... 

ALDEHYDES Bis(4-methylpiperazinyl)aluminum hydride. Di(r) -cyclopentadienyl)-(chloro)hydridozitconium(IV). Dihalobis(triphenylphosphine)paIIadium(H). 7,8-Dimethyl-l,5-dihydro-2,4-benzodithiepin. Grignard reagents. Lithium bis(ethylene-dioxyboryOmethide. 3-Methyl-I-phenyl-2-phospholene. 2-Methyl-2-thiazoline. Methylthioacetic acid. 3-Methylthio-l,4-diphenyl-s-triazium iodide. Sodium meth-oxide. Methylthiomethyl N,N-dimethyldithiocarbamate. Sodium tetracarbonylferrate(II). Tetra-n-butylammonium borohydride. Triethylallyloxysilane. N,4,4-Trimethyl-2-oxazolinium iodide. 

Toluene diisocyanate (TDI), 54 C2CI4, 500 1 -Phenyl-3-methyl-phospholene oxide. 120 4 — b... 

MDI, 675, + Phenylisocyanate, 71.4 C2CU 3-Methyl-1 -phenyl-2-phospholene 1-oxide, 1.87 120 4 e... 

Isophorone diisocyanate, 231.2, and butyl isocyanate, 68.8 Amylacetate, 270 1 -Phenyl-3-methyl-2-phospholene oxide, 30 g of 10% soln in xylene 140 26 g... 

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