5-methyl- 1,2,4-triphenyl

Quebrachitol was converted into iL-c/j/roinositol (105). Exhaustive O-isopropylidenation of 105 with 2,2-dimethoxypropane, selective removal of the 3,4-0-protective group, and preferential 3-0-benzylation gave compound 106. Oxidation of 106 with dimethyl sulfoxide-oxalyl chloride provided the inosose 107. Wittig reaction of 107 with methyl(triphenyl)phos-phonium bromide and butyllithium, and subsequent hydroboration and oxidation furnished compound 108. A series of reactions, namely, protection of the primary hydroxyl group, 0-debenzylation, formation of A-methyl dithiocarbonate, deoxygenation with tributyltin hydride, and removal of the protective groups, converted 108 into 7. 

Methyl triphenyl phosphonium bromide (0.56 mmol) was dissolved in 10 ml of THF and treated with 1.6 M -butyl lithium (0.64 mmol) in hexane solution at 0°C. The solution was stirred for 30 minutes at 0°C and then treated with the step 2 product (0.36 mmol) and stirred an additional 2 hours at ambient temperature. The solution was treated with dilute hydrochloric acid, extracted with chloroform, dried over MgSC>4, and concentrated. The residue was purified by silica gel column chromatography using chloroform/hexane, 2 1, respectively, recrystallized using CH2CI2/ methanol, and 100 mg of product isolated. 

An S-methyl(triphenyl)dithioformate complex of platinum(O) has been prepared from Pt(C2H4)(PPh3)2 and Ph3SnC(S)SMe.1873... 

Another highly versatile building block derived from diacetone-glucose 54 is the 1,2-acetonide of 3-C-methyl-a-D-allose in its furanoid form 57, which has been utilized as the key compound in a convergent total synthesis of ACRL Toxin I (63). Its elaboration from 54 starts with a pyridinium dichromate / acetic anhydride oxidation (64), is followed by carbonyl olefination of the respective 3-ulose with methyl (triphenyl)phosphonium bromide and hydrogenation (— 55 56), and is completed by acid cleavage of the 5,6-isopropylidene group. This four-step process 54 -> 57, upon optimization of reaction conditions and workup procedure, allows an overall yield of 58 % (63), as compared to the 22 % obtained previously (65). 

Auch Methylen-triphenyl-phosphoran bildet unter Anlagerung von Alkoholen Alkoxy-methyl-triphenyl-phosphorane, die bei iefen Temperaturen kristallin isoliert werden kon-nen15 ... 

Entspreehend erhalt man u.a. Ethoxy- (51% Zers. ab — 75°) bzw. Isopropyloxy-methyl-triphenyl-phosphoran (67% Zers. ab —70°). 

Methyl-propyloxy- Xll/l, 323 (2-Methyl-propyloxy)-phenyl- XII/1, 322 E2,189 Methyl-triphenyl- E2, 66 Octyl- XII/1, 157, 293 Phenoxy-phenyl- XII/1, 321 E2,131 Phenyl-propyloxy- E2, 422 Phenyl-(2-triethylstannyl-ethyl)- E2,170 Phenyl-trimethylsilyloxy- El, 274 Propyloxy- E2, 181 Triallyl- XII/1, 159... 

Etho. y-difluor-hydro-(4-methyl-phenyl)- E2, 837 Ethoxy-difluor-hydro-phenyl- E2, 837 Ethoxy-methyl-triphenyl- E2, 884 Ethoxy-tetramethyl- E2, 884 Ethyl-hydro-isopropylthio-4-(2-phenyl-hydrazono)-E2, 294... 

Hydro-(4-methyl-phcnyl)-trifluor- E2, 837 Hydro-methyl-trifluor- E2, 836 Flydro-organo-trifluor- E2, 835 Hydro-phenyl-trifluor- E2, 837 Hydro-trifluor-trifluormethyl- E2, 837 Hydroxy-methyl-triphenyl- XII/1, 106 Hydroxy-tetrabenzyl- XII/1, 106 Hydroxy-tetraethyl- XII/1, 106 Isopropyloxy-methyl-triphenyl- E2, 884 Isopropyl-tetrachlor- E2, 430 Methoxy-methyl-triphenyl-... 

E. (TV V-DIETHYLDISELENOCARBAMATO)METHYL(TRIPHENYL-PHOSPHINE)PLATINUM(II),PtCH3(PPh3XSe2CNEt2)... 

NPPtSejCaHa, Platinum(II), (AUV-diethyldise-lenocarbamato)methyl( triphenyl-phosphine)-, 21 10... 

E8sig8 ure [4 acetoxy 2 methyl-triphenyl e8sig8 ure] anhydrid 10, 369. 

Bhise s patent [53] describes a process for preparing and separating ethylene glycol from an aqueous solution of ethylene oxide using supercritical carbon dioxide. Supercritical fluid extraction (T < 100°C p < 295 bar) removed most of the ethylene oxide and a little water into carbon dioxide, which formed directly the feedstock for carbonation (catalysed by methyl triphenyl phosphon-ium iodide at 20-90°C). Sufficient water was then supplied for hydrolysis. Carbon dioxide, both that produced in the hydrolysis step and the original solvent, was partially vented for recycle, liberating the ethylene glycol product and the reaction catalyst. 

How does the rate of decomposition of diazene N-oxide 7 compare with the corresponding diazene, Direct measurement of the rate of decomposition of methyl benzhydryldiazenecarboxylate, Sy was complicated by tautomerization to the corresponding hydra-zone, Ph2C=NNHC02CH3. The rate of decomposition of was estimated from the measurement rate of decomposition of benzhydryl-phenyldiazene (24) and the observation that the rates of decomposition of phenyltriphenylmethyldiazene and methyl triphenyl-methyldiazenecarboxylate are the same (21). Relative rates of 7, 8, and a related nitrone, 9 (25) are summarized below. ... 

In addition, phosphonium salts were reported by the group of Plumetto catalyze the TMSCN addition to aldehydes [73] and ketones [74]. Methyl(triphenyl)phos-phonium iodide [73] was an active catalyst for the addition of TMSCN to aldehydes at room temperature. The yields after 24 h were between 70% and 97%, depending on the aldehyde applied in the reaction (Scheme 16.26). However, the salt did not catalyze the addition of TMSCN to ketones. An exception was the highly reactive cyclobutanone [75]. 

Fit securely to the lower end of the condenser (as a receiver) a Buchner flask, the side-tube carrying a piece of rubber tubing which falls well below the level of the bench. Steam-distil the ethereal mixture for about 30 minutes discard the distillate, which contains the ether, possibly a trace of unchanged ethyl benzoate, and also any biphenyl, CeHs CgHs, which has been formed. The residue in the flask contains the triphenyl carbinol, which solidifies when the liquid is cooled. Filter this residual product at the pump, wash the triphenyl-carbinol thoroughly with water, drain, and then dry by pressing between several layers of thick drying-paper. Yield of crude dry product, 8 g. The triphenyl-carbinol can be recrystallised from methylated spirit (yield, 6 g.), or, if quite dry, from benzene, and so obtained as colourless crystals, m.p. 162. ... 

TEST Aniline 0- toluidine m-> toluidine P-. toluidine I- naphthyl- amine 2- naphthyl- amine mono- methyl- aniline diphenyl- amine dimethyl- aniline triphenyl- amine... 

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