Methyl 3,4-0-benzylidene chloride

Bis-[methoxy-methyl]-diethyl- -chlorid E14a/2, 180 (N-Methoxymethylierung) (a-Brom-benzyliden)-dialkyl- E5, 39 (R — CO — NR2 + COBr2)... 

SYNS BENZYL DICHLORIDE BENZYLENE CHLORIDE BENZYLIDENE CHLORIDE BENZYLIDENE CHLORIDE pOT) CHLOROBENZAL CHLORURE de BENZYLIDENE piCHLORO-METHYL)BENZENE a-a-DICHLOROTOLUENE RCRA WASTE NUMBER U017 TOLUENE, a-a-DICHLORO-... 

Benzoic acid Benzoic anhydride Benzonitnle Benzophenone 3,4 Benzopvrene Benzopyrene Benzoyl acetone Benzovi chloride Benzyl acetate Benzyl alcohol Benzylamine Benzvl chloride Benzyl formate Benzyhdeneaniline Benzylidene chloride Benzylidenemethylamme Benzyl methyl ketone Bibenzyl... 

In a structural study of the products from reaction of methyl jS-D-cellobioside with benzylidene chloride in pyridine, simultaneous relaxation and doubleresonance experiments were carried out. This novel technique allowed couplings to be assigned to protons normally superimposed by multiplets... 

Acetophenone Methyl Phenyl Ketone 1-Phenyl Ethanone Benzyl Dichloride Benzylidene Chloride... 

Acylation of the heterocyclic enamines e.g., l,3,3-trimethyl-2-methyl-eneindoline (126) and 2-benzylidene-3-methylbenzothiazoline (42) takes place normally at the methylene carbon (42,69), with both acyl and aroyl chlorides in the presence of base. 

Treatment of methyl 2-azido-4,6-0-benzylidene-2-deoxy-a-D-altro-pyranoside (128) (42) with 121 followed by refluxing and processing afforded a chloro derivative as a sirup in 70% yield (46, 49). Reduction of this product with an excess of Raney-nickel in methanol containing acetic anhydride afforded a crystalline product, m.p. 179°C., which is formulated as the d-manno analog 131. The actual product is most likely methyl azido-4,6-0-benzylidene-3-chloro-2,3-dideodxy - a - d - mannopyran-oside (130) resulting from attack of chloride ion at C-3 with inversion of configuration in the intermediate 129. Had the chlorination proceeded... 

Trimethylbenzenesulfonyl chloride has been shown21 to be much more selective for the monosulfonylation of a vicinal secondary diol (for example, methyl 4,6-O-benzylidene-a-D-gluco-pyranoside) than p-toluenesulfonyl chloride, and, apparently, 2,4,6-triisopropylbenzenesulfonyl chloride exhibits an even higher selectivity.22... 

Ethoxycarbonyl chloride is, by virtue of resonance involving the ester function, less reactive than acetyl chloride, and the reagent has found application for selective O-acylation in the steroid field.34 With this reagent, methyl 4,6-O-benzylidene-a-D-glucopyranoside yielded35 2- and 3-esters in the ratio 24 1, and the related benzyl-thiocarbonyl chloride gave the 2-ester in 58% yield.36... 

Esterification of several methyl 4,6-O-benzylidene-D-hexo-pyranosides with one molar equivalent of benzoyl chloride-triethylamine in an inert solvent was found to occur with good selectivity, mainly affording 2-benzoates from the a-D-gluco, a-D-allo, and a-D-altro compounds, and the 3-benzoate from the j8-D-gluco compound.52... 

Reactivity at 0-3, in addition to that at 0-4 and 0-6, was observed with methyl )3-D-galactopyranoside, which, when treated with sulfuryl chloride, yielded methyl 3,4,6-trichloro-3,4,6-trideoxy-/J-D-allopyranoside 2-(chlorosulfate) in 56% yield.352 In contrast, under similar conditions, methyl a-D-galactopyranoside gave352 methyl 4,6-dichloro-4,6-dideoxy-a-D-glucopyranoside 2,3-di(chlorosulfate). Further examples of the dependence of the reactivity on the configuration of C-l are the conversion of methyl 4,6-0-benzylidene-/3-D-glucopyranoside into methyl 4,6-0-benzylidene-3-chloro-3-deoxy-/3-i>allopyranoside by sulfuryl chloride,352 and of methyl 4,6-0-benzylidene-a-D-glucopyranoside, under similar conditions, into the 2,3-di(chlorosulfate).355... 

Trimethyl phosphite (11.3 g, 0.091 mol) was added to a solution of 3-benzylidene-2,4-pentanedione (16.35 g, 0.091 mol) in dry methylene chloride. The solution was maintained under nitrogen for 24 h at 20°C and for an additional 5 h at 40°C. After this time, the solvent was evaporated, and the residue was dissolved in hexane. These actions were performed in the absence of moisture. The clear hexane solution was seeded with a crystal of the pure crystalline product (obtained by crystallization from hexane by standing for 2 weeks at 0°C), and after 8 h at 0°C the crystals precipitated yielding pure 2,2,2-tri-methoxy-3-phenyl-4-acetyl-5-methyl-A4-oxaphospholene (25.12 g, 88.4%) of mp 48-51°C. 

Volatile alkyl halogenides such as methyl iodide, methylene chloride etc., react quantitatively with the solid methylamine salt of 5-benzylidene- (39a) [32] and 5,5-diphenylthiohydantoin (37) to form the anticonvulsive solids 225 and 226 in quantitative yield [28] (Scheme 30). Unlike the solution reaction, only the S-alkylation occurs under gas-solid conditions. Furthermore, various dialkylamidodithiolate salts 228 react readily with dichloromethane at 80 °C. The salts with the quaternary cations react at room temperature and it is also possible to catalyze the reaction of the sodium salt by admixture of 10% of the corresponding phase transfer bromides [28]. These reactions have been tuned for removal of dichloromethane from loaded air streams [28]. 

The reaction of 39 with methyl 4,6-0-benzylidene-2-deoxy-2-iodo-a-D-altropyranoside (48) gave a complex mixture of products, from which methyl 4,6-0-benzylidene-2,3-dideoxy-a-D-eryf/iro-hex-2-eno-pyranoside (50) could be isolated. The formation of 50 was ex-plained83(b) by attack by chloride ion on the iodine atom in intermediate 49, followed by elimination of the substituent at C-3. Compound 50 itself reacts with reagent 39, and, therefore, prolonged reaction times led to extensive decomposition. 

A novel method of opening of oxiranes involves the use of (chlo-romethylene)dimethyliminium chloride (39) [see Section II,2c p. 250], monochlorodeoxy or dichlorodideoxy derivatives are obtained, depending upon the reaction conditions employed.83 Thus, methyl 2,3-anhydro-4,6-0-benzylidene-a-D-allopyranoside (110) reacts with 39 in 1,1,2,2-tetrachloroethane at room temperature to give, upon hydrolysis of the primary adduct 111 with an aqueous solution of sodium hydrogen carbonate, methyl 4,6-0-benzylidene-2-chloro-2-deoxy-3-0-formyl-a-D-altropyranoside (112). If a solution of 39 and 110 in 1,1,2,2-tetrachloroethane is heated at reflux temperature, methyl 3,4-0-benzylidene-2,6-dichloro-2,6-dideoxy-o -D-altropyrano-side (113) is obtained in high yield the n.m.r. spectrum of 113, like that of 47 (see Section II, 2c p. 250), showed the presence of two diastereoisomers which differed in the configuration of the benzyl-idene-acetal carbon atom. 

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