Methyl 4-formylbenzoate

Methyl 4-formylbenzoate, benzylamine, 2-nitrobenzoic acid, and cyclohexyl isocyanide were converted to the corresponding 4CC Ugi adduct [16],... 

The testing of 2-nitrobenzyltriphenylphosphonium bromide and methyl 4-formylbenzoate and four other aldehydes, 3-benzyloxybenzaldehyde, 2-naphthaldehyde, 5-nitrothiophene-2-carboxaldehyde and 4-[3-dimethylamino)propoxy]benzaldehyde, has been reported [13]. 

P 58] Another protocol focused on continuous contacting of the two reactant solutions. Again, flow was fed by electroosmotic means [13]. A 0.01 M methanol solution of 2-nitrobenzyltriphenylphosphonium bromide was used a 0.02 M methanol solution for methyl 4-formylbenzoate with sodium methoxide (0.015 M) was used. Volumes of 80 pi of both solutions were set in the respective reservoirs on the chip and 40 pi of methanol in the collection reservoir. A voltage of 400 V was applied for both feed lines. The reactions were carried out at room temperature and run for 20 min. 

For methyl 4-formylbenzoate, the yield decreased from 70% (2 1) to 59% (1 1) [13]. For batch processing, the yield decreased from 60% (2 1) to 48% (1 1), i.e. the reductions were similar. In both cases, micro channel processing was superior. 

Basic alumina (13 g) was added to a mixture of methyl 4-formylbenzoate Id (1.00 g, 6 mmol) and acetophenone 2 (0.48 g, 4 mmol) at room temperature. (When the reactants were solid, a minimum amount (2x3 mL) of dichloro-metliane was used to dissolve them prior to the addition of the alumina.) The reaction mixture was then agitated at room temperature for 2.5 h using a Fisher vortex mixer. The product was extracted into dichloromethane (5x15 mL). Removal of the solvent, under reduced pressure, yielded the solid product. Further purification (removal of traces of benzyl alcohol and aldehyde) was carried out by recrystallization from a petroleum ether-ether mixture to afford l-phenyl-3-[4-(carbomethoxy)phenyl]-2-propen-1-one 3d (4-carbomethoxychalcone), mp 119— 120 °C (81%). 

Haswell and coworkers carried out the Wittig reaction of 2-nitrobenzyl triphenylpho-sphonium bromide with methyl 4-formylbenzoate in a microflow system [17,18]. They used a borosilicate glass microreactor with T-shaped channels (width = 200 pm and depth = 100 pm), and the reagents were added via EOF by applying a constant... 

Sodium triacetoxyborohydride (3.80 mmol) was added to a solution of the Step 2 product (1.90 mmol) and methyl 4-formylbenzoate (1.90 mmol) in 5 ml CH2C12 and the mixture stirred overnight at ambient temperature. The mixture was then treated... 

C9H7N04 p-nitrocinnamic acid, predominantly trans 619-89-6 25.00 1.3674 2 16228 C9H803 methyl 4-formylbenzoate 1571-08-0 25.00 1.2467 2... 

Cl1 HI402 benzyl 2-methyipropanoate 103-28-6 501.15 43.995 1,2 22198 C11H1404 methyl 4-formylbenzoate dimethyl acetal 42228-16-0 520.32 45.840 2... 

Benzoic acid, 4-formyl-, methyl ester p-Carbomethoxybenzaldehyde CCRIS 6063 EINECS 216-385-5 p-Formylbenzoic acid methyl ester HSDB 5842 Methyl 4-formylbenzoate Methyl p-formylbenzoate Methyl benzaldehyde-4-carboxylate Methyl terephth-aldehydate NSC 28459 Terephthalaidehydic acid, methylester. 

Reagents and conditions i) 2-nitrobenzyl bromide, DMF, 70°C ii) a) Na2S20<, EtOH, reflux, b) HBr, MeOH, dioxane Hi) PMB chloride, py, CHsCIs iv) methyl 4-formylbenzoate, NaOMe, MeOH, reflux v) aminomethyl resin, AcOH, MeOH/dioxane vi) NaOMe, MeOH, reflux vii) toluene, DMF, distillation viii) KOtBu, reflux. 

Synthesis of diaryl heteroarotinoids (11) and (12) [27,30,31] began with a Lewis acid-catalyzed cyclization of tertiary alcohol (34) to give dihydroben-zothiophene (36) as the sole isolated product. The chemistry of the ensuing steps was similar to that used to prepare (9) and (10) and other diaryl heteroarotinoids and involved (a) Friedel-Crafts acylation of a fused aromatic-heterocyclic system, (b) reduction of the resulting ketone to a benzylic carbinol, (c) phosponium salt formation, and finally (d), Wittig coupling to methyl 4-formylbenzoate. The free acids (13) and (14) were obtained by saponification. 

The final coupling step involved either an aldol-like condensation of germyl-substituted acetophenone (114) with methyl 4-formylbenzoate or involved condensation of substituted anilines with aroyl chlorides. 

---