Methyl benzoate, synthesis

The synthesis of pyrazolines and pyrazoles of the [CCNN + C] type with the creation of two bonds, N(2)-C(3) + C(3)-C(4) (or N(l)-C(5) + C(5)-C(4)), has been studied by several groups. Beam and coworkers have published a series of papers on the synthetic utility of lithiated hydrazones. Thus, the methylhydrazone of acetophenone (598) is converted by butyllithium into the dianion (599), which in turn reacts with methyl benzoate to afford the pyrazole (600) (76SC5). In earlier publications Beam et al. have used aldehydes and acyl chlorides to obtain pyrazolines and pyrazoles by the same method. 

Farhi, M., Dudareva, N., Masci, T. et al. (2006) Synthesis of the food flavoring methyl benzoate by genetically engineered Saccharomyces cerevisiae. Journal of Biotechnology, 122, 307-315. 

This study was next extended to the synthesis of benzoyl and dodecanoyl derivatives from protected carbohydrates [67]. Microwave-assisted PTC transesterifications with methyl benzoate or dodecanoate were studied for several carbohydrates. Small amounts of dimethylformamide (DMF) were shown to be necessary to provide good yields (76-96%) within 15 min. Rate enhancements when compared to conventional heating (A) and specific microwave activation were especially noticeable when less reactive fatty compounds were involved (Eq. 48). 

An optimised enzymatic synthesis of methyl benzoate in an organic medium was reported by Leszczak and Tran-Minh [43]. Methyl benzoate is part of the aroma of some exotic fruits and berries. The ester has been produced by direct esterification of benzoic acid with methanol in hexane/toluene catalysed by lipase from Candida rugosa. 

Aminolysis of phenyl dithioacetates,8 pyridinolysis of O-ethyl dithiocarbonates,9 reaction of pyrrolidine with O-ethyl 5-aryl dithiocarbonates,10 aminolysis of chlorothionformates,11 pyridinolysis of alkyl aryl thioncarbonates,12 reaction of anionic nucleophiles with nitrophenyl benzoate and its sulfur analogues,36 hydrolysis of methyl benzoate and phenyl acetate containing SMe, SOMe and S02Me substituents,42 solvolysis of phenyl chlorothioformate,79 synthesis of new thiadiazoles,124 examination of a neighbouring sulfonium group in ester hydrolysis,136 hydrolysis of V-type nerve agents,250 and the reactions of peroxymonosulfate ion with phosphorus(V) esters have all been looked at previously in this review. 

The reaction can be also applied to azoles (e.g., imidazoles, pyrazoles, triazoles, tetrazole) as the N -nucleophile for the hydroaminations of cyclic olefins. In this case, the presence of methyl benzoate sensitizes the photoisomerization of the double bond to form a highly strained ( )-cycloalkene. Protonation of this intermediate by triflic acid (TfOH, 20mol%) and addition of the azole nucleophile completes the reaction sequence [41]. As an example, the expeditious synthesis of l-(l-methylcy-clohexyl)- H-imidazole (27) in 72% yield is shown in Scheme 3.17 [41]. 

Ballini, R., Barboni, L., Fiomi, D., Giarlo, G., and Pahnieri, A. 2005c. One pot synthesis of 3,5-alkylated acetophenone and methyl benzoate derivatives via an anionic domino process. Chemical Communications, 20 2633. ... 

This hydrogenation is particularly useful for stereoselective synthesis of the (El-C,-exocyclic trisubstituted double bond of carbaeyclin. Thus hydrogenation of the 1,3-diene 3 catalyzed by (methyl benzoate)Cr(CO), can resi.lt in the desired product 4 in yields as... 

Devise a synthesis of each compound from methyl benzoate (C6H5CO2CH3) and organic alcohols having three or fewer carbons. You may also use any organic or inorganic reagents. 

Acylations. Catalyzed by graphite the Friedel-Crafts acylation as well as the transformation of ethers to esters by acyl halides in refluxing 1,2-dichloroethane are realized. Although aliphatic chlorides are inferior to aromatic halides this method is quite general as shown by the synthesis of benzoates (e.g., allyl benzoate from allyl benzyl ether and methyl benzoates from methyl f-butyl ether). 

Under the same basic conditions /ra . -l-acetoxymethyl-1-methyl-2-tosylcyclopropane generated an a-sulfonyl anion, which attacked the ester group intramolecularly and afforded 2,5-dimethyl-l-tosyl-3-oxabicyclo[3.1.0]hexan-2-ol (22) in 50% yield.Stereoselective synthesis with a chiral cyclopropyl sulfoxide was experienced when ( )-4-tolylsulfinylcyclopropane was reacted first with butyllithium and then with methyl benzoate and gave 1-benzoyl-1-[(5)-4-tolylsulfinyl]cyclopropane (23a) in 62% yield. A useful reaction took place when 2-(hy-droxymethyl)cyclopropyl phenyl sulfide was treated first with an excess of butyllithium and then with dimethylformamide and gave 2-hydroxy-l-phenylsulfanyl-3-oxabicyclo[3.1.0]hexane (24), a lactol which has been used to carry out various useful synthetic transformations. Another useful reaction occurred when cyclopropyl phenyl sulfones were treated with butyllithium followed by an acyl imidazole to give acyl cyclopropanes in decent yield. 

A13-00525 Benzoic acid, methyl ester CCRIS 5851 Clorius EINECS 202-259-7 Essence of niobe FEMA No, 2683 HSDB 5283 Methyl benzenecarboxylate Methyl benzoate Methylester kyseliny benzoove Niobe oil NSC 9394 Oil of niobe UN2938. Used in perfumery, as a solvent for cellulose esters and ethers, resins, rubber flavoring. Liquid mp = -15° bp = 199° d = 1.0933 insoluble in H2O, soluble in organic solvents Xm = 228,272,280 nm (s = 11000, 830, 686, MeOH) LDso (rat orl) n 1177 mg/kg. Lancaster Synthesis Co. Morflex Penta Mfg. Pentagon Chems. Ltd Sybron. 

The Tebbe reagent is quite useful in that it reacts with the carbonyl of esters to give vinyl ethers. Pine showed that 683 reacted with methyl benzoate to give an 81% yield of 1-methoxy-l-phenylethene. O Similar reaction of lactone 686 with 683 gave the exo-methylene vinyl ether 687 in Holmes synthesis of (+)-laurencin.571 The Tebbe reagent also reacts with conjugated esters via 1,2-addition to give the vinyl ether. ... 

Synthesis of Aromatic Nitriles from Esters. A one-flask method has been developed for the conversion of aromatic esters to the corresponding nitriles by use of NaHMDS in a sealed tube at 185 °C in a mixture of THF and 1,3-dimethyl-2-imidazolidinone (DMEU) (eq 20). The transformation proceeded with good to excellent yields. The synthetic strategy is only apphcable to aromatic esters that bear an electron-donating substituent such as hydroxy or methoxy. In the latter case, con tetitive 0-demethyla-tion is observed, thus leading to a mixture of nitrile products. The reaction has been also applied to indole-3-carboxylate. However, simple unsubstituted methyl benzoate failed to give the desired product. 

A soln. of benzoic acid in hexane percolated through a column containing Amberlite IRA 904 (OH-), a macroreticular resin containing quaternary ammonium groups, the resin then placed in a flask, a soln. of methyl iodide in hexane added, and stirred 2 hrs. at room temp. methyl benzoate. Y 90%. F. e., also in water and other solvents, and from tosylates, s. G. Cainelli and F. Manescalchi, Synthesis 1975, 723. 

Starting from bromobenzene, provide a short synthesis of methyl benzoate (C5H5CO2CH3). 

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