Cyclohexane carboxaldehyde

Concern for the conservation of energy and materials maintains high interest in catalytic and electrochemistry. Oxygen in the presence of metal catalysts is used in CUPROUS ION-CATALYZED OXIDATIVE CLEAVAGE OF AROMATIC o-DIAMINES BY OXYGEN (E,Z)-2,4-HEXADIENEDINITRILE and OXIDATION WITH BIS(SALI-CYLIDENE)ETHYLENEDIIMINOCOBALT(II) (SALCOMINE) 2,6-DI-important industrial method, is accomplished in a convenient lab-scale process in ALDEHYDES FROM OLEFINS CYCLOHEXANE-CARBOXALDEHYDE. An effective and useful electrochemical synthesis is illustrated in the procedure 3,3,6,6-TETRAMETHOXY-1,4-CYCLOHEX ADIENE. ... 

To a solution of trimethylsilylmethyl lithium (from chloromethyltrimethyl-silane (15.8mmoI) and lithium dispersion (196mmol)) in ether (30ml) was added cyclohexane carboxaldehyde (14.2 mmol) at ambient temperature, with stirring. After a further 10min at ambient temperature, the solution... 

Conjugate addition, 34-5, 51-2,53, 132, 133 Conjugate hydroxymethylation, 59-60 Copper(n) bromide, 54 Copper([) chloride, 120 Copper(n) chloride, 120 Copper(i) cyanide, 7,52, 53 Copper(i) iodide, 54 Corey s internal quench, 104 Cyanohydrin trimethylsilyl ether, 137 Cycloaddition. 34,112 Cydobutane-l,2-dione, 135 Cyclohept-2-dione, 135 Cyclohex-2-enone, 52,123 Cyclohcxa-1,3-diene, 26 Cyclohexane carboxaldehyde, 22-3,69 73,78... 

To a stirred solution of the epoxysilane (1 mmol) in THF/water (3 ml, 4 1) was added perchloric acid (0.1 ml, 70%), and stirring was continued for 4 h at ambient temperature. The mixture was then poured into water (20ml), and extracted with dichloromethane (3 x 20 ml). Drying and concentration gave cyclohexane carboxaldehyde (0.71 mmol, 71%). 

TIPSCH2C=CTIPS (preparation given, but not detailed) was metallated (21) by treatment with n-BuLi in hexane (1 eq.) in THF at -20 °C for 15 min. Addition of cyclohexane carboxaldehyde (1 eq.) to the anion in THF at -78 °C was followed by gradual warming to ambient temperature over 6 h. Normal extraction procedures followed by chromatography on silica gel afforded the (Z)-enyne, 71%, >20 1 (Z) ( ). 

Trimethylsilyloxy)methylene]cyclohexane was prepared from the corresponding carboxaldehyde according to the method of House.4a b Cyclohexane carboxaldehyde was obtained from the Aldrich Chemical Company, Inc., and purified by distillation at atmospheric pressure (bp 160-164°C). 

The utility of -phenyl camphor-derived oxazolidinones as chiral formyl anion syn-thons has been demonstrated by Gawley and coworkers (Scheme 42). Deprotonation yields a dipole-stabihzed organolithium intermediate and the absolute configuration of the lithium-bearing carbon is presumed to be R. Additions to benzaldehyde and cyclohexane carboxaldehyde are 86% and 76% diastereoselective, respectively, but recrystallization affords a single diastereomer in the yields shown. Addition is postulated to proceed via the pre-complex shown in the inset, in which the aldehyde is coordinated to the R epimer... 

Figure 6.54 Structures of guanidine-based thiourea derivatives screened in the Henry reaction of nitromethane with cyclohexane carboxaldehyde under phase-transfer conditions.

Figure 6.55 Uncharged tris-thiourea 190 without guanidinium moiety and charged guanidinium structure 191 without a thiourea group appeared catalytically inactive in the Henry reaction of cyclohexane carboxaldehyde with nitromethane, while guanidine-thiourea 183 gave 99% yield and 95% ee under identical (optimized) conditions.

Enholm reported radical-anionic sequences involving ketyl radical cyclisa-tions that culminate in intermolecular aldol reactions treatment of aldehyde 24 and cyclohexane carboxaldehyde with Sml2 triggers a radical cyclisation-intermolecular aldol sequence to give 25 in good yield (Scheme 6.10).15... 

In the reaction.s of allenylindium and allenylzinc reagents 392 and 391 derived from (R)-3S9, formation of the anti homopropargylic alcohol 393 is favored and highest levels of diastereoselectivity are obtained with branched aldehydes (e.g. cyclohexane carboxaldehyde. Table 11-22). The anti stereochemistry of adducts 393 indicates that these reactions occur through cyclic transitions state in a manner similar to the reactions of the trichloroallenylstannane reagent 226 (see above, Scheme 11-27). 

Marshall subsequently demonstrated that the efficiency of the crotylation reactions catalyzed by CAB catalyst 459b could be improved by using the more reactive crotylstannanes and employing two equivalents of (CF3C0)20 to aid catalyst turnover [310]. In a comparative study of the catalytic asymmetric allylation and crotylation reactions of cyclohexane carboxaldehyde with allyl- and crotylstannanes 98 and 10, Marshall demonstrated the complementarity between the BINOL-Ti(0-i-Pr)4 catalyst 451 and the CAB catalyst 459b (Table 11-29). 

Cyclohexane carboxaldehyde (98% Purity from Sigma-Aldrich)... 

A mixture of cyclohexane carboxaldehyde (0.11 g, 1 mmol) and indium powder (0.17 g, 100 mesh, 1.5 mmol) in water (0.11 ml, 6 mmol) was added crotyl bromide (0.16 g, 1.2 mmol) slowly at room temperature in 5-mL round-bottomed flask. The reaction mixture was stirred for 12 hours followed by heated at 40 °C and monitored by TLCl3 until all the adduct was converted into its linear regioisomer. Ether was added to dilute the reaction mixture followed by 1 M hydrochloric acid to quench the reaction. The reaction mixture was extracted with ether. The combined organic layer was washed with brine, and dried over anhydrous magnesium sulfate, filtered and the solvent was removed in vacuo. 

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