3- Methoxy-4-nitrobenzaldehyde

A series of 11 nitrobenzaldehydes was examined by TGA, DSC and ARC techniques. Only 5-hydroxy-2-nitrobenzaldehyde decomposed exothermally in an unsealed container, but all did so in sealed capsules, under dynamic, isothermal or adiabatic conditions, with evolution of much gas. Initial decomposition temperatures in °C (compound, ARC value, and DSC value at lOVmin, respectively, followed by ARC energy of decomposition in kJ/g) were - 2-nitro-, 176, 220, 1.44 3-nitro-, 166, 218, 1.94 4-nitro-, 226, 260, 1.27 2-chloro-5-nitro-, 156, 226, 697 2-chloro-6-nitro-, 146, 220,. 832 4-chloro-3-nitro-, 116, 165, 1.42 5-chloro-2-nitro-, 240, 3-hydroxy-4-nitro-, 200, 4-hydroxy-3-nitro-, 200, 5-hydroxy-2-nitro-, 175, 3-methoxy-4-nitrobenzaldehyde, 245°C, -. 4-Nitrobenzaldehyde showed by... 

The reaction has been carried out on large- and small-scale batches (Note 10). This modification, as exemplified by 3,4,5-trimethoxybenzaldehyde, has been applied by the submitters to the preparation of other aldehydes such as 3,4-dimethyl-benzaldehyde (90% yield), 3-benzyloxy-4,5-dimethoxybenz-aldehyde (88% yield, with retention of the benzyl group), and 3-methoxy-4-nitrobenzaldehyde (62% yield, with retention of the nitro group). 

Problem 19,6 p-Nitrobenzaldehyde is more reactive toward nucleophilic additions than />methoxy-benzaldehyde. Explain. 

The synthesis of other biologically active thiazoles was described by Ohsumi et al. [50] and is shown in Scheme 16. Condensation of phosphonium bromide and 4-methoxy-3-nitrobenzaldehyde gave a 1 1 mixture of (Z)- and (-E)-stilbenes. ( )-stilbene 64 was purified by crystallization and then converted to bromohydrin 65 by NBS-H2O. Oxidation of the bromohydrin by DMSO-TFAA gave the bromoketone intermediate 66, which was condensed with thiocarbamoyl compounds in the presence of Na2C03 in DMF to give the corresponding 2-substituted thiazole derivatives (67a and b). Compound 67a... 

A frequently reported spectrophotometric technique for the determination of hydralazine is based on reactions with aromatic aldehydes to form hydrazones with absorption in the visible region. Luk yanchikova et al (5 +) used p-nitrobenzaldehyde Wesley-Hadzija and Abaffy (55) and Ruggieri (56) used p-dimethylaminobenzaldehyde Luk yanchi-kova (57,58) used cinnamaldehyde Schulert (33) used p-hydroxybenzaldehyde and Zak et al (59) used p-methoxy-benzaldehyde, after testing cinnamaldehyde, salicylaldehyde, 3, +,5-trimethoxybenzaldehyde, and 1-naphthaldehyde. 

Acetoxy-3-methoxybenzaldehyde, 3290 4-Acetoxy-3-methoxy-2-nitrobenzaldehyde, 3266 f Acrylaldehyde, 1145... 

Preparative hazards have been noted for the following compoimds 4-Acetoxy -3 -methoxy-2-nitrobenzaldehyde, 3266 Acetyl chloride, 0735 Aluminium copper(I) sulfide, 0084... 

Cohare and co-workers reported that aristolactam BU (22) was prepared, following Kupchen s method, by Perkin condensation of 6-bromo-3,4-di-methoxy phenyl acetic acid (119) and o-nitrobenzaldehyde (120) (Scheme 14). The 2-bromo-4,5-dimethoxy-2 -nitro-ds-stilbene-a-carboxylic acid (121) was obtained. The nitro group of 121 was reduced with ferrous sulfate and ammonium hydroxide, and the resulting 2-bromo-4,5-dimethoxy-2 -amino-cw-stilbene-a-carboxylic acid (122) without purification was submitted to the Pschorr phenanthrene synthesis to yield l-bromo-3,4-dimethoxyphen-anthrene-lO-carboxylic acid (123). The phenanthrylamine 124 was prepared from 123 via a Schmidt reaction, and, by treatment with n-butyllithium and CO2, 124, afforded 22 (42). 

The reaction product of dimethyl malonate and 1,6-hexanediol with dimethyl-aminobenzaldehyde, 4-methoxy-benzaldehyde, and 3-nitrobenzaldehyde was previously prepared by the authors (2) and used in ophthalmic applications. 

Acetoxy-3-methoxy-2-nitrobenzaldehyde, 3260 4-Acetoxy-3-methoxybenzaldehyde, 3284 f Acrylaldehyde, 1142 4-Azidobenzaldehyde, 2693 f Benzaldehyde, 2727 f Butyraldehyde, 1602 5 -Chloro-2-nitrobenzaldehyde, 2648 4-Chloro-3-nitrobenzaldehyde, 2647... 

This group covers aromatic nuclei bearing one nitro group most mono-nitro benzenes can be persuaded to detonate by a tetryl booster few are an immediate danger in the absence of other sources of energy. Calorimetric studies [1] suggest that nitroaryl compounds decompose by an autocatalytic mechanism, and thus stability may depend upon thermal history. Individually indexed compounds are 4-Acetoxy-3-methoxy-2-nitrobenzaldehyde, 3260 2-Amino-5-nitrophenol, 2309... 

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