2-Chloro-6-nitro benzaldehyde

The complexes ML2, where M = Co, Cu, Ni, Zn HL = 2-hydroxy-5-(chloro/ nitro)-benzaldehyde[4-(3-methyl-3-mesitylcyclobutyl)-l,3-thiazol-2-yl]hydra-zone, give IR spectra indicating chelation of L through azomethine N and phenolate O atoms.509 Coordination of the 5-(2 -carboxyphenylazo)-8-hydro-xyquinoline to Co, Ni, Cu or U022+ via CN, N=N, COOH and OH was shown by IR spectroscopy.510 IR data for M(II) (=Co, Ni, Cu, Zn) complexes of A -salicyloyl-A"-/)-hydroxythiobenzohydrazide and related ligands show coordination by thiolato S, enolic O and two hydrazine N atoms.511... 

The second-order rate constants for the reaction of OH radical with meta- and para-isomers of hydroxy-, methoxy-, chloro- and nitro-benzaldehydes are in the range (2.8 to 12) x 10 dm mol s . The higher rate in methoxybenzaldehyde is attributed to the activation of the ring by the electron-donating -OCH3 group. 

Although acridone was not first synthesized by Lehmstedt, it was Lehmstedt who extensively explored the methods for the preparation of acridones, including the reaction between anthranilic acid and chloro-nitrobenzene, desulfurization of thioacridone by copper, and treatment of ortho-nitro benzaldehyde with chloro-nitrobenzene and sulfuric acid. Among these methods, the one between o-nitrobenzaldehyde and halobenzene is known as the Lehmstedt-Tanasescu method or Lehmstedt-Tanasescu reaction. In addition, this preparation of acridone is also referred to as the Tanasescu synthesis. ... 

In 1972, van Leusen, Hoogenboom and Siderius introduced the utility of TosMIC for the synthesis of azoles (pyrroles, oxazoles, imidazoles, thiazoles, etc.) by delivering a C-N-C fragment to polarized double bonds. In addition to the synthesis of 5-phenyloxazole, they also described reaction of TosMIC with /7-nitro- and /7-chloro-benzaldehyde (3) to provide analogous oxazoles 4 in 91% and 57% yield, respectively. Reaction of TosMIC with acid chlorides, anhydrides, or esters leads to oxazoles in which the tosyl group is retained. For example, reaction of acetic anhydride and TosMIC furnish oxazole 5 in 73% yield. ... 

These reaction conditions also permit the chemoselective quantitative reduction of benzaldehyde to benzyl alcohol without any concomitant reduction of either acetophenone or 3,3-dimethylbutan-2-one present in the same reaction mixture.83 Additionally, this useful method permits the reduction of aldehyde functions in polyfunctional compounds without affecting amide, anhydride, eth-ylenic, bromo, chloro, or nitro groups.79,80,319... 

A compound (40), isolated from the reaction between 2-chloro-5-nitro-pyridine and tert-butyl jV-hydroxycarbamate, has been shown to react with benzaldehyde to give 6-nitro-2-phenyl-triazolopyridine (41)53 5-nitro-2-pyridone acts as a leaving group. 

On the other hand, when electron-attracting p-nitro, p-chtom, phenyl groups were present, the benzaldehyde carbonyl waa wrfK-ciently activated to give the expected products, p-nitro, p-chloro-, utul p-phenylbenzalacetophcnono oxide respectively (Eq. 1 0). 

N 14.41%. Four isomers are described in the literature 2-Chloro-3-hydroxy-, orn-red ndls(from dil ale), mp 244-45° 4-Chloro-3-hydroxy, violet red ndls(from dil ale), mp 226-27° 6-Cbloro-3 -hydroxy-, red ndls(from dil ale), mp 250-51° and 2-Chloro-3-hydroxy-benzaldehyde-(4 -nitro-phenylhydrazone, red ndls (from ale or AcOH), mp 288°(dec). Other props methods of prepn are given in the Refs... 

Condensations of erythritol with benzaldehyde,78,78 o-, wi-andp-chloro-benzaldehyde,18 p-methylbenzaldehyde,18 p-methoxybenzaldehyde,18 o-, m- and p-nitrobenzaldehyde,18,87 3-nitro-4-chlorobenzaldehyde,18 acetaldehyde,74 chloroacetaldehyde,74 acetone,1718 formaldehyde,78 and val-eraldehyde76 have been reported, but in no case has the structure of the product been determined. The physical constants of these acetals and ketals are recorded in Table VII. The photo-sensitivity of o-nitrobenzyl-idene-erythritols has been discussed on page 149. 

CH.NOji It yel crysts, mp 98-99° readily sol in org soivs except petr eth insol in w was prepd by nitrating 2-nitro 4-chlorocinnamic acid with HN03(d 1.52), or by reacting 2-nitro-4-chloro-benzaldehyde with nitromethane KOH in MeOH-KOH(Refs 2 4) and... 

Chloro-3-nitro-2-phenylchroman-4-ones, available from various benzaldehydes, are readily both dechlorinated and denitrated to flavanones on reaction with Bu3SnH in a radical process initiated by AIBN <97SYN1305>. In the presence of boric acid and piperidine, silica gel effects the conversion of 2, 6 -dihydroxyacetophenones and benzaldehydes into 5-hydroxyflavanones <97H(45)71>. 

A recent study has examined the antimicrobial activity of various aldehydes against M. tuberculosis [107]. Pentenal, benzaldehyde and phthalalde-hyde showed a kill greater than 10 cfu ml" in 5 minutes, though benzaldehyde was only active in the presence of 2% glutraldehyde. Substituents (nitro, chloro, methyl and methoxy) on the benzaldehyde ring reduced this synergism, but still showed increased activity over 2% glutaraldehyde alone [107]. 

N-(5-Ghloro-3-nitro-2-hydroxybenzoyl) -N -isonicotinoylhydrazine dissolved in water-methanol on a water bath, benzaldehyde added, and boiled 5 min. l-(5-chloro-3-nitro-2-hydroxybenzoyl) -2-isonicotinoyl-3-phenylaziridine. Y 90%. F. e. s. C. von Plessing, Arch. Pharm. 297, 240 (1964). 

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