2-Chloro-6-fluorobenzaldehyde

CjjHjClFN 367-27-5) see Norfloxacin Pefloxacin 2-chloro-6-fluorobenzaldehyde (C7H4CIFO 387-45-1) see Flucloxacillin 2-chloro-6-lluorobenzaldehyde oxime (C7H5CIFNO 443-33-4) see Flucloxacillin... 

C7H4CIFO 2-chloro-6-fluorobenzaldehyde 387-45-1 25.00 1.3310 2 9803 C7H4F3N02S 2-nitro-4-(trifluoromethyt)benzenethiol 14371-82-5 25.00 1.5190 2... 

The structure of retinaldehyde (2) was also modified by similarly substituted phenyl rings. 2-Chloro-6-fluorobenzaldehyde (219), was reacted with the C5 phosphonate (220) in the form of the PO-activated ylid, two steps being required to build the tetraene side chain (Matsumoto et al, 1980). In each case the nitrile group was reduced to a formyl group using diisobutyl aluminum hydride. 

Gas-phase basicities of several substituted benzaldehydes (62 X = o-/m-/p-Me/F, o-j 77 -Cl) have been measured, relative to benzaldehyde or mesitylene as reference bases, over a range of temperatures.101 The tolualdehydes are more basic than benzaldehyde, the halobenzaldehydes less so, following classical aromatic substituent effects. The data also correlate well with solution-based linear-free-energy substituent constants, as well as with theoretical (MNDO) calculations. Some deviations are noteworthy (i) the o-halobenzaldehydes (especially chloro) have higher basicities than predicted, but calculations tend to rale out the hydrogen-bonded isomer (63), which is also contraindicated by a normal A,S value, inconsistent with the expected restriction of— hOH rotation in such a structure (ii) anomalies in the high-temperature behaviour of m-fluorobenzaldehyde in the presence of mesitylene reference base are consistent with a specific catalysed isomerization to the ortho- or para-isomer. 

Potassium carbonate (5.53 g) was added to 2-chloro-4-fluorobenzaldehyde (3.35 g) and 3-benzyloxyphenol (4.23 g) dissolved in 70 ml DMF and the solution and stirred for 3 hours at 150°C. The mixture was decanted into water, then extracted with EtOAc, washed with water and brine, dried with Na2S04, and concentrated. The residue was purified by chromatography with silica gel using hexane/EtOAc, 6 1, and 6.73 g product isolated as a colorless powder. 

C7H4CIFO 4-chloro-2-fluorobenzaldehyde 51072-56-f 25.00 1.3310 2 9800 C7H4F3N02 1-nitro-2- trifluoromethyl)benzene 384-22-5 25.00 1.3910 2... 

C7H4CIFO 2-chloro-4-fluorobenzaldehyde 84194-36-5 25.00 1.3310 2 9805 C7H4F3N03 4-nitro-3-(trifluoromethyl)phenol 88-30-2 25.00 1.5120 2... 

Benzene can be formylated very easily. Fluorobenzene gives fluorobenzaldehyde with a total selectivity in para isomer. On the contrary chloro and bromobenzene are transformed in poor yield, and chloro and bromo toluenes 17 are obtained next to halobenzaldehydes 16, showing that methyl formate can act as an alkylating agent. 

Benzylideneaminoacetoaldehyde acetals prepared from benzaldehydes have been key intermediates of a well-established method for isoquinoline synthesis known as the Pomeranz-Fritsch reaction (Scheme 16, route a) [49,50], Intramolecular cycliza-tion of this type of imines under acidic conditions provided isoquinolines, where the two-carbon substituent on the nitrogen atom was transformed into a part of the isoquinoline ring. For the synthesis of 8-fluoroisoquinohne, the application of the standard procedure gave a low yield of the desired product (3 % in two steps from 2-fluorobenzaldehyde) [51]. However, in the modified procedure using ethyl chloro-formate, trimethyl phosphite, and titanium tetrachloride for the cyclization step [52] provided 6-fluoroisoquinoline from 4-fluorobenzaldehyde in 34 % overall yield (Scheme 17) [25],... 

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