Methyl acetate from acetyl chloride

The chemical operations described in the literature to introduce or into citric acid molecule are based essentially on the Grimaux and Adam synthesis. Labeled citric acid was prepared by Wilcox et al. [35] in the reaction of Na CN with 3-chloro-2-carboxy-2-hydroxybutyric acid and the formed nitrile was hydrolyzed directly with hydrochloric acid. From this solution, citric acid was isolated in the form of calcium citrate and finally converted to the acid. An alternative procedme was proposed by Rothchild and Fields [36] to obtain trimethyl citrate from labeled sodium cyanide and di-chloromethyl glycolate. A more complex synthesis of C labeled citric acid is described by Winkel et al. [39]. They used labeled methyl acetate and acetyl chloride (in the presence of hthium 1,1,1,3,3,3,-hexamethyldisilazide, [(CH3)2Si]2NLi which was dissolved in tetrahydiofuran) to obtain methyl acetoac-etate. It reacts in the presence of lithium diisopropylamide, [(CH3)2CH]2NLi, also dissolved in tetrahydrofuran, with dimethyl carbonate to give dimethyl 1,3-ace-tonedicaiboxylate. It is dicarboxylated by the action of bisulfite and potassium cyanide is converted to 3-cyano-3-hydroxy-l,5 pentanedioate and finally hydrolyzed by hydrochloric acid to citric acid. 

N-Methyl-N-f2-Nitroxy propyl) Nitramine. (Me2NENA N-(2-NitroxypropyI) methyl nitramine. (02N)N(CH3).(CH2CH(0N02).CH3, mw 179.16, N 23.46%, OB to C02 -66.80%, pale yellow oil, mp 22—23°, d 1.320g/cc at 25/4°, RI 1.478 at 25°. Prepn from 2-hydroxy-propylamine after nitration with 98% nitric acid at 10° by reaction of the amine-nitric acid mixt with acetic anhydride acetyl chloride at 35°. Reaction mixt poured on ice. Yield is 74%. No expl properties listed Reft 1) Beil - not found 2) Blomquist, OSRD 4134, 45 119 (1944)... 

One way to investigate the electrophilic properties of these molecules is to examine the orbital that each uses to accept electrons from a nucleophile. This orbital is the lowest-unoccupied molecular orbital (LUMO). Examine the LUMO for methyl acetate (Z=OCH3), acetaldehyde (Z=H), N,N-dimethylacetamide (Z=N(CH3)2) and acetyl chloride (Z=C1) (acetaldehyde is not a carboxylic acid derivative, but is included here for comparison). What is the shape of the LUMO in the region of the carbonyl group Is it a o or 7U orbital Is it bonding or antibonding What other atoms contribute to the LUMO Which bonds, if any, would be weakened when a nucleophile transfers its electrons into the LUMO ... 

A molecule with a low energy LUMO can accept electrons more readily than a molecule with a higher energy LUMO. The LUMO energies (in au) for the above molecules ai e 0.192 (methyl acetate), 0.161 (acetaldehyde), 0.212 (N,N-dimethylacetamide), and 0.132 (acetyl chloride). Order these molecules from most electrophilic to least electrophilic. 

The chiral acetate reagent is readily prepared from methyl mandelate [methyl (A)-hydroxy-phenyl acetate] which is first converted by treatment with phcnylmagnesium bromide into the triphenylglycol783, c (see Section 1.3.4.2.2.2.) and subsequently transformed into the acetate by reaction with acetyl chloride in the presence of pyridine. Thereby, the secondary hydroxyl group of the glycol is esterified exclusively. Both enantiomers of the reagent are readily accessible since both (R)- and (5)-hydroxyphenylacelic acid (mandelic acids) arc industrial products. 

Apart from the reaction of cyclohexanecarboxylic acid with methyllithium, cyclohexyl methyl ketone has been prepared by the reaction of cyclohexylmagnesium halides with acetyl chloride or acetic anhydride and by the reaction of methylmagnesium iodide with cyclohexanecarboxylic acid chloride. Other preparative methods include the aluminum chloride-catalyzed acetylation of cyclohexene in the presence of cyclohexane, the oxidation of cyclohexylmethylcarbinol, " the decarboxylation and rearrangement of the glycidic ester derived from cyclohexanone and M)utyl a-chloroj)ropionate, and the catalytic hydrogenation of 1-acetylcycIohexene. "... 

The A-methyl-A -arylazoaminoacetonitriles (194) and hydrogen chloride in ether yield the 1,2,3-triazolium chlorides (195). These salts (195) and base did not give the corresponding meso-ionic compounds (193, R = Me, R == Ar, R = R = H), but the corresponding J acetyl derivatives (193, R = Me, R = Ar, R = H, R = Ac) were produced either from the nitriles (194) and acetyl chloride or from the 1,2,3-triazolium chlorides (195) and acetic aidiydride, followed by treatment with ammonium hydroxide. ... 

C9H10O, Mr 134.18, mp 28 °C, Z> ioi.3kPa 226 °C, df 1.0051, nf 1.5335, has been identified in Brazilian rosewood oil and in pepper. It occurs as colorless crystals with a flowery-sweet odor that is milder than that of acetophenone. 4-Methyl-acetophenone is prepared from toluene and acetic anhydride or acetyl chloride by... 

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