O Chlorobenzaldehyde

In a 47 per cent yield from o-chlorobenzaldehyde, sodium, and carbon dioxide. Morton, LeFevre, and Hechenbleikner, J. Am. Chem. Soc. 58, 754 (1936). 

Although thiosalicylaldehyde 46a (R2 = H) was first synthesized by Friedlander and Lenk (Scheme 23),95 it is an unstable intermediate and should be stored in solution below 0°C. Alternate synthetic procedures utilizing o-chlorobenzaldehyde or salicylaldehyde, as starting materials, are shown in Scheme 24.96 The preferred method for the synthesis of substituted thiosalicylaldehydes 46 is via salicylaldehyde. 

The Claisen-Schmidt condensation of 2 -hydroxyacetophenone and different chlorinated benzaldehydes over MgO has been investigated through kinetic and FTIR spectroscopic studies. The results indicate that the position of the chlorine atom on the aromatic ring of the benzaldehyde substantially affects the rate of this reaction. In particular, the rate increases in the following order p-chlorobenzaldehyde < m-chlorobenzaldehyde < o-chlorobenzaldehyde. The difference between the meta and para-substituted benzaldehyde can be attributed to electronic effects due to the difference in the Hammett constants for these two positions. Steric effects were found to be responsible for the higher rate observed with the o-chlorobenzaldehyde. 

Additional adsorption studies were also carried out using para- and ortho-chlorobenzaldehydes (Figure 4). The results obtained with p-chlorobenzaldehyde are very similar to the ones obtained with m-clilorobenzaldehyde and were omitted from this paper for brevity. In contrast, substantial differences are observed in the spectra of adsorbed o-chlorobenzaldehyde. In particular, in this case the 1620 cm"1 band characteristic... 

Figure 4 FTIR spectra of o-chlorobenzaldehyde adsorbed on MgO (a) After lmin exposure of o-chlorobenzaldehyde at 70°C (b) after 20 min exposure of o-chlorobenzaldehyde at 70°C (c) after 5 min exposure at 110°C and (d) after 5 min exposure at 160°C.

To the methods listed in Org. Syn. 16, 68 (Coll. Vol. 2, 1943, 523), may be added the hydrolysis of 2-chlorophthalide 2 and the action of carbon dioxide and sodium, under pressure, upon o-chlorobenzaldehyde.3 The procedure described is essentially that of Racine.4... 

Cations, cyclopropenyl, 54, 97 o-Chlorobenzaldehyde, by reduction of o-chlorobenzonitrile with Raney nickel alloy in formic acid, 51, 23 p-Chlorobenzaldehyde, by redaction of p-chlorobenzonitflle with Raney nickel alloy,1 51, 22... 

Cloxacillin Cloxacillin, [2S -(2a,5a,6j3)]-3,3-dimethyl-7-oxo-6-[(5-methyl-3-(o-chlor-phenyl)-4-isoxazolcarboxamido)]-4-thia-l-azabicyclo[3.2.0]-heptan-2-carboxylic acid (32.1.1.11), is synthesized from o-chlorobenzaldehyde by the scheme described above [21-23,25]. 

We developed a method for the synthesis of a variety of cyclic acetals that utilizes bismuth triflate as a catalyst and does not require the use of a Dean-Stark trap for removal of water [102]. In this method, an aldehyde or ketone is treated with 1,2-bis (trimethylsiloxy)ethane in the presence of bismuth triflate. A comparison study using o-chlorobenzaldehyde showed that with ethylene glycol a low conversion to the dioxolane was observed after 2 h whereas the use of the 1,2-bis(trimethylsiloxy) ethane afforded the corresponding dioxolane in good yields. (Scheme 9). 

Figure 6.9 Bifunctional 3-amino quinuclidine derivatives 30 and 31 and DABCO probed in the MBH reaction between methyl acrylate and o-chlorobenzaldehyde.

Ballantyne et al. examined the ocular effects of CS in polyethylene glycol-CPEG) solutions, as a powder, and as smokes. Test solutions were made up in concentrations of 0.5, 1, 2, 5, and 10Z CS in PEG. Each was tested on 10 rabbits with 0.1-ml drops instilled into one eye. Four groups of 20 rabbits were tested at 0.5, 1, 2, and 5 mg of CS as a powder. Ten rabbits were exposed to CS grenade smoke for 15 min the average CS concentration was 6 g/m3. The effects of the hydrolysis products of CS were also examined. Ten animals were tested with o-chlorobenzaldehyde and 10 with malono-nitrile. The amounts of the two compounds were determined as the ratio obtained by the hydrolysis of a 5Z solution of CS. This was a... 

Sodium cyanide, Glacial acetic acid, Chlorine gas. Carbon tetrachloride Benzene, Aluminum chloride, 2-Chloroacetyl chloride. Hydrochloric acid. Sodium hydroxide. Methylene chloride. Calcium chloride. Hexanes Methanol, MalononitrUe, o-Chlorobenzaldehyde, Piperdine Tetrahydrofuran, Hydrogen chloride, Chloropicrin, Powdered tin Benzene, Arsenic trichloride. Aluminum chloride. Hexanes Acetone, Sulfuric acid. Chlorine, Calcium chloride Isopropylamine, Glyoxal, Diethyl ether Benzene, Pyridine, Diphenylamine, Arsenic trichloride Tetraethyl lead. Arsenic trichloride... 

Intramolecular addition to benzyne generated from the Schiff base of aniline and o-chlorobenzaldehyde is thought to involve addition of an amide anion to the C=N bond [163]. This mechanism indicates donor accentuation of the ortho carbon. 

Chloro-6-azauraci1, AB22 o-Chlorobenzaldehyde, AI92 -Chlorobenzaldehyde, A 193 2-Chlorobenzaldehyde, k 92 U-Chlorobenzaldehyde, A193... 

Use of o-nitrobenzaldehyde as the aldehyde was particularly successful [261] and use of other aromatic aldehydes as substrates, e.g. o-chlorobenzaldehyde, also worked well [262]. 

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