Benzaldehyde, 2,4,6-trimethyl

Benzaldehyde, o nitro, 46,81 Benzaldehyde, 2,4,6-trimethyl-, 47,1 Benzaldehydes, halogen- and methyl-substituted, preparation from diazomum salts and formal doxime, 46, IS... 

Improved procedure. A soln. of benzaldehyde, trimethyl borate, and tetrahydrofuran injected at 25° through a septum inlet to Zn-metal under Ng followed by ethyl bromoacetate in one portion with stirring, which is continued 12 hrs. 

The aldol reaction of 2,2-dimethyl-3-pentanone, which is mediated by chiral lithium amide bases, is another route for the formation of nonracemic aldols. Indeed, (lS,2S)-l-hydroxy-2,4,4-trimethyl-l-phenyl-3-pentanone (21) is obtained in 68% ee, if the chiral lithiated amide (/ )-A-isopropyl-n-lithio-2-methoxy-l-phenylethanamine is used in order to chelate the (Z)-lithium cnolate, and which thus promotes the addition to benzaldehyde in an enantioselective manner. No anti-adduct is formed25. 

AcetaUzation of benzaldehyde with trimethyl orthoformate can be carried out with a series of MOFs constructed from In and BDC or BTC ligands with open In sites. The catalysts are even stable in aqueous medium and can be reused without loss of activity. Owing to the small pores of these MOFs, the reaction only takes place at the outer surface of the crystals [54]. In another MOF constructed from In and 4,4 -(hexafluoroisopropylidene)bis(benzoic acid), the same reaction takes place inside the pores [55]. 

Whereas aldehydes such as benzaldehyde or ketones are converted by trimethyl-silylated alkyl- or aryl-mercaptans such as 575, in the presence of catalytic amounts of cyanide, to give high yields to O-trimethylsilyl-hemithioketals such as... 

It is supposed that the nickel enolate intermediate 157 reacts with electrophiles rather than with protons. The successful use of trimethylsilyl-sub-stituted amines (Scheme 57) permits a new carbon-carbon bond to be formed between 157 and electrophiles such as benzaldehyde and ethyl acrylate. The adduct 158 is obtained stereoselectively only by mixing nickel tetracarbonyl, the gem-dibromocyclopropane 150, dimethyl (trimethylsilyl) amine, and an electrophile [82]. gem-Functionalization on a cyclopropane ring carbon atom is attained in this four-component coupling reaction. Phenyl trimethyl silylsulfide serves as an excellent nucleophile to yield the thiol ester, which is in sharp contrast to the formation of a complicated product mixture starting from thiols instead of the silylsulfide [81]. (Scheme 58)... 

The PhSiH3/RhCl(PPh3)3 combination reduces trimethyl orthobenzoate to the dimethyl acetal of benzaldehyde with small amounts of methyl benzyl ether product (Eq. 315) 493... 

Adapted from Sasidharan and Kumar (257). Reaction conditions catalyst, 150 mg methyl trimethyl-silyl dimethylketene acetal (silyl enol ether), 10 mmol benzaldehyde, 10 mmol dry THF as dispersion medium, 10 mL temperature, 333 K reaction time, 18 h. Yield refers to the isolated product yield. Moles of product per mole of metal per hour. b The metal atom is substituted in the tetrahedral position. 

The reactions of complex 2a with ketones and aldehydes show a strong dependence on the substituents. With benzophenone, substitution of the silyl-substituted acetylene leads to the r]2-complex 58, which is additionally stabilized by a THF ligand. This complex can serve as an interesting starting material for other reactions. With benzaldehyde and acetophenone, the typical zirconadihydrofuran 59, akin to 2c, is obtained from a coupling reaction. This complex is unstable in the case of benzaldehyde and dimerizes, after elimination of bis(trimethylsilyl)acetylene, to yield 60. In this respect, it is similar to the above discussed complex 2c, since both of them show a tendency to eliminate the bis(trimethyl-silyl)acetylene. The reaction of methacrolein with complex 2a depends strongly on the solvent used [40]. 

Extracts of the male oil palm bunch moths, Tirathaba mundella Walker (Lepidoptera Pyralidae), were shown to contain four compounds namely, 5S, 65)-2,2,6-trimethyl-6-vinyl-tetrahydro-pyran-3-ol, 4-hydroxy-3-methoxy benzaldehyde (vanillin), 6,10,l4-trimethyl-2-pentadecanone, and the corresponding alcohol 6,10,l4-trimethyl-2-pentadecanol, which elicited responses from the females. However, when synthetic compounds were used in lures, the ketone and alcohol by themselves did not attract females, suggesting that they might not be an essential part of the blend. This can only be confirmed once their absolute configuration has been determined and the proper stereoisomers tested in the... 

In the Mukaiyama aldol additions of trimethyl-(l-phenyl-propenyloxy)-silane to give benzaldehyde and cinnamaldehyde catalyzed by 7 mol% supported scandium catalyst, a 1 1 mixture of diastereomers was obtained. Again, the dendritic catalyst could be recycled easily without any loss in performance. The scandium cross-linked dendritic material appeared to be an efficient catalyst for the Diels-Alder reaction between methyl vinyl ketone and cyclopentadiene. The Diels-Alder adduct was formed in dichloromethane at 0°C in 79% yield with an endo/exo ratio of 85 15. The material was also used as a Friedel-Crafts acylation catalyst (contain-ing7mol% scandium) for the formation of / -methoxyacetophenone (in a 73% yield) from anisole, acetic acid anhydride, and lithium perchlorate at 50°C in nitromethane. 

A weak base such as glycine added to [HMIMjPFg has also been reported to catalyze a Knoevenagel reaction of malononitrile and benzaldehyde 110). A KOH-treated [BMIMjPFg also provides a suitable medium for the Corey-Chaykovsky epoxidation of enones and cyclopropanation of aldehydes using trimethyl sulfonium iodide (///). 

Ethanone, 1- [3-(l,l-dimethylethyl)-4-methoxy-5-nitrophenyl Benzaldehyde, 2 (l,l-dimethylethyl)-4-methoxy-5-nitro Benzene, 1,4-BIS- (1, l-dimethylethyl)-2 methoxy-5-nitro Benzene, 1-(1, l-dimethylethyl)-2, 5-dimethoxy-4-nitro Benzene, 1-(1, l-dimethylethyl)-2-methoxy-4 methyl-5-nitro Benzaldehyde, 5- (1, l-dimethylethyl)-2-methyl-3-nitro Benzaldehyde, 2- (1, l-dimethylethyl)-4,5,6-trimethyl-3-nitro Benzene, 5-(l, l-dimethylethyl)-2-methoxy-l, 3-dinitro Benzene, 1-(1, l-dimethylethyl)-4-methoxy-2-methyl 3-5-dinitro Benzene, 2-bromo-5- (1, l-dimethylethyl)-4-methoxy-l,... 

Several examples of Bi(0Tf)34H20-catalyzed Mannich-type reactions of various A-benzyloxycarbonylamino sulfones 1 with silyl enol ethers are summarized in Table 5. A-Benzyloxycarbonylamino sulfones 1 derived from differently substituted benzaldehydes were reacted with trimethyl(l-phenylvinyloxy)silane in dichloromethane at room temperature. The corresponding (3-amino ketones 24 were smoothly obtained (Table 5, entries 1-6). The reaction was efficient using electron-deficient benzaldehyde-derived sulfones, and the corresponding (3-amino ketones 24... 

Pinacol rearrangement driven by the release of the ring strain of a cyclobutane ring has been employed in an extremely efficient manner to form cyclopentanone derivatives. Experimentally. the Lewis acid mediated aldol condensation of benzaldehyde with l,2-bis(trimethyl-siloxy)cyclobutcne at —78 C gave the pinacol 1 in its silylated form.35,36 Subsequent treatment of this pinacol with trifluoroacetic acid at room temperature afforded 2-phenyl-cyclopentane-l,3-dione (2) in 97% yield.35,36... 

Lithium bis(trimethylsilyl)amide Disilazane, 1,1,1,3,3,3-hexamethyl-, lithium salt (8) Silanamine, 1,1,1-trimethyl-N-(trimethylsilyl)-, lithium salt (9) (4039-32-1) Benzaldehyde (8,9) (100-52-7)... 

Benzaldehyde phenylhydrazone with DM AD gave 8% of dimethyl 1,3-diphenylpyrazole-4,5-dicarboxylate (136) together with 35% of trimethyl pyrazoletricarboxylate (138), which the authors suggest is obtained from the primary adduct 137 by Michael addition of a second mole of DMAD followed by cleavage, as shown.129... 

Solid-Phase Synthesis Terminated by Diketopiperazine Cyclative Cleavage (Scheme 1). The Fmoc-L-Trp resin (loading 0.5 mmol/g) is first deprotected with 20% piperidine in DMF for 20 min, and the resin washed and dried. The resin ( 1 g, 0.62 mmol/g) is shaken with benzaldehyde (0.63 ml, 10 molar equiv.) and trimethyl orthoformate (1.36 ml, 20 molar equiv.) in 7 ml CH2C12 overnight, followed by washing and drying to give resin 1. 

Highly porous silica gel served as a support for the TADDOL moiety derived from inexpensive and readily available i-tartaric acid, which provided access to htanium-based Lewis acid catalysts (Heckel, 2000). Such entihes are employed successfully for enantioselective reactions. TADDOLs were covalently attached to the trimethyl-silyl-hydrophobized silica gel, controlled-pore glass (CPG) at about 300 m2 g-1, at a loading of 0.3-0.4 mmol gl (Heckel, 2002). In a carefully monitored mulh-step immobilization procedure, the TADDOLs were titanated to yield dichloro-, diisopropyl-, or ditosyl-TADDOLates. These catalysts were employed in dialkylzinc addihon to benzaldehydes and diphenyl nitrone addihon to 3-crotonyloxazolidinone, a [3+2] cycloaddition. 

Component 1 in Singapore buildings was correlated with compounds associated with humans and their activities. Human effluents have been reported to contain isoprene (Ellin et al, 1974) while tetrachloroethylene is a VOC found in dry-cleaned clothes worn by building occupants (Wallace, Pellizzari and Wendel, 1991) or from the use of consumer products (Sack et al., 1992). Tetradecane, benzaldehyde, o-xylene, naphthalene are emissions from dry process photocopiers (Leovic et al., 1996). Component 2 with high loadings ofn-decane, n- undecane, toluene, styrene, n-nonane, 1,2,4-trimethyl benzene probably reflects the emissions of carpets and vinyl floorings (Yu and Crump, 1998). Component 3 was primarily correlated with heptane and methylcyclopentane, which could be due to the emissions of water-based paints. Finally, component 4 was associated with 2-methylpentane, hexane, cyclohexane, methylcyclohexane and limonene, which is reflective of the emissions of air fresheners and cleaning products (Sack et al., 1992). 

In the Vilsmeier formylation of iV-( 3-hydroxyethyl)anilines the hydroxyl group is simultaneously replaced by chlorine [60], The resulting aldehydes condense with l,3,3-trimethyl-2-methyleneindoline to form very brilliant dyes [61], With 4-(W-methyl-iV- 3-chloroethylamino)benzaldehyde a commercial dye is obtained. A methyl group in the 2-position to the methine chain produces a bluish-red color (27). 

Distyrylbiphenyls, discovered in 1967, can be produced in a similar way to distyrylbenzenes [34], The reaction of 4,4 -bis(chloromethyl)biphenyl with trimethyl phosphite yields 4,4 -bis(dimethoxyphosphonomethyl)biphenyl [27344-43-0. Reaction with, for example, benzaldehyde-2-sulfonic acid gives 4,4 -di(2-sulfostyryl)biphenyl disodium salt (10) [27344-41-8],... 

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