3-Phenylpropan

Give the structure of the expected organic product in the reaction of 3 phenylpropanal with each of the following... 

The bridged radical A has been suggested as a possible intermediate in the photochemical decarbonylation of 3-phenylpropanal. Suggest an experiment to test this hypothesis. 

Dibenzylamino)-3-phenylpropanal adds benzyllithium reagents with virtually complete steric approach controlled selectivity again the simple diastereoselectivity is poor (approx. 1 11 2)5. 

The crude product obtained from the reaction of (4S,5/J)-2.2-diethyl-4-methyl-5-phenyloxazolidinc [bp 95-100 °C/0.5 Torr [a]u° —60.0 (r = 23, CIIC13)] and 3-phenylpropanal (according to the procedure above) is stirred with 3 mL of acetone and a catalytic amount of BF3 OEt, overnight. After evaporation oT the acetone the residue is purified by chromatography (silica gel, hexane/EtOH) yield 77% 92% ee [a] 8 +18.8 (c = 2.2, CHC13). 

This and similar catalysts are effective with silyl ketene acetals and silyl thioketene acetals.155 One of the examples is the tridentate pyridine-BOX-type catalyst 18. The reactivity of this catalyst has been explored using a- and (3-oxy substituted aldehydes.154 a-Benzyloxyacetaldehyde was highly enantioselective and the a-trimethylsilyoxy derivative was weakly so (56% e.e.). Nonchelating aldehydes such as benzaldehyde and 3-phenylpropanal gave racemic product. 3-Benzyloxypropanal also gave racemic product, indicating that the (i-oxy aldehydes do not chelate with this catalyst. 

Chemat et al. have reported several microwave reactors, including systems that can be used in tandem with other techniques such as sonication [68], and ultraviolet radiation [69]. With the microwave-ultrasound reactor, the esterification of acetic acid with n-propanol was studied along with the pyrolysis of urea. Improved results were claimed compared with those from conventional and microwave heating [68]. The efficacy of the microwave-UV reactor was demonstrated through the rearrangement of 2-benzoyloxyacetophenone to l-(2-hydroxyphenyl)-3-phenylpropan-l,3-dione [69]. 

Chemat and his collaborators [92] reported the UV- and MW-induced rearrangement of 2-benzoyloxyacetophenone, in the presence of bentonite, into l-(o-hydroxy-phenyl)-3-phenylpropane-l,3-dione in methanol at atmospheric pressure (Sch. 14.2). The reaction, performed in the reactor shown in Fig. 14.7, was subject to a significant activation effect under simultaneous UV and MW irradiation this corresponded at least to the sum of the individual effects (Fig. 14.11). The rearrangement, however, was not studied in further detail. Such competitive processes can be described by the diagram in Fig. 14.9, because the product obtained from both types of activation was the same. 

Superior yields of ethers from aldehydes are obtained by the use of several other electrophilic species. The addition of 5 mol% of trityl perchlorate to a mixture of triethylsilane and 3-phenylpropanal in dichloromethane at 0° produces an 83% yield of bis-(3-phenylpropyl) ether within 10 minutes (Eq. 176),329 Reductive polycondensation of isophthalaldehyde occurs with two equivalents of triethylsilane in the presence of 10 mol% of trityl perchlorate to give 40-72% yields of polyether with average molecular weights ranging from 6,500 to 11,400 daltons (Eq. 177).337 Addition of one equivalent of an alkoxytrimethylsilane to the reaction mixture produces unsymmetrical ethers in good to excellent yields. Thus, a mixture of (ii)-cinnamaldehyde, 3-phenylpropoxytrimethylsilane, and triethylsilane in dichloromethane reacts under the influence of a catalytic amount of trityl perchlorate to give the unsymmetrical ether in 88% yield (Eq. 178).329... 

TMEDA and bipyridine also gave the corresponding complexes. Amoung those complexes, only 120 was found to react smoothly with 3-phenylpropanal to give 119 in good yield. When the aldehyde and the acetylene of Scheme 51 were replaced with acetone and dipentylacetylene, respectively, the corresponding allylic tertiary alcohol could be obtained in 83%. 

To a solution of the titanocene(II) reagent 29 in THF (42 mL) in a 300-mL round-bottomed flask, prepared from titanocene dichloride (6.54 g, 26.3 mmol), magnesium turnings (0.766 g, 31.5 mmol), triethyl phosphite (8.96 mL, 52.5 mmol), and finely powdered 4 A molecular sieves (1.31 g) according to the procedure described above, was added a solution of l,l-bis(phenylthio)cyclobutane (63 2.29 g, 8.40 mmol) in THF (14 mL). The reaction mixture was stirred for 15 min. and then a solution of (S)-isopropyl 3-phenylpro-panethioate (91 1.46 g, 7.00 mmol) in THF (21 mL) was injected dropwise over a period of 10 min. The reaction mixture was refluxed for 1 h, then cooled, whereupon 1 m aq. NaOH solution (150 mL) was added. The insoluble materials produced were removed by filtration through Celite and washed with diethyl ether. The aqueous layer was separated and extracted with diethyl ether. The combined ethereal extracts were dried (Na2S04), filtered, and concentrated. The residual liquid was purified by column chromatography (silica gel, hexane) to afford 1.33 g (77%) of (l-isopropylthio-3-phenylpropan-1 -ylidene) cyclobutane (92). 

BtURET, 1-PHENYL-2-THIO-, 42,87 Bromination, of 2-aminopyridine, 44,34 of l-bromo-3-phenylpropane with N-bromosuccinimide to give 1,3-dibromo-l-phenylpropane,... 

The l-bromo-3-phenylpropane was obtained from Columbia Organic Chemicals Co., Inc., Columbia, South Carolina, and from Aldrich Chemical Co., Inc., Milwaukee, Wisconsin. Redistillation of the commercial material does not noticeably affect yields. 

Gas chromatographic analysis at 155° on a 5 ft. 5% SE-30 column shows only the presence of 2,2-dimethyl-3-phenylpropanal and solvent. 

Bromo-3-phenylpropane Benzene, (3-bromopropyl)- (8,9) (637-59-2) Triphenylphosphine Phosphine, triphenyl- (8,9) (603-35-0)... 

Preparation of Enantiomerically Pure a-N,N-Dibenzylamino Aldehydes S-2-(N,N-Dibenzylamino)-3-phenylpropanal. 

Phenylpropyltriphenylphosphonium bromide (1) was prepared using the following procedure A solution of 1 equiv of 1-bromo-3-phenylpropane and 1.05 equiv of triphenylphosphine (both obtained from Aldrich Chemical Company, Inc.) in dry toluene is heated at reflux for 50 hr. The resulting solids are collected by vacuum filtration, washed on the filter three times with dry pentane, and dried at 100°C/1 mm for 6 hr affording 1 in 87-92%yield. 

Reductive metallation of aldehydes (but not ketones) by tri-n-butyl-(trimethyisilyl)stannane to yield a-hydroxystannanes is catalysed by tetra-n-butylammonium cyanide [15]. Other phase-transfer catalysts are not as effective and solvents, other than tetrahydrofuran, generally give poorer conversions. Use of a chiral catalyst induced 24% ee with 3-phenylpropanal. 

SYNTHESIS OF AN a-HYDROXYAMIDE N.N-DIETHYL-2-HYDROXY-4-PHENYLBUTANAMIDE. GENERATION OF N,N-DIETHYLCARBAMOYLLITHIUM VIA LITHIUM-TELLURIUM EXCHANGE AND ITS REACTION WITH 3-PHENYLPROPANAL (Benzenebutanamide, N,N-dlethyl-a-hydroxy-)... 

The submitters used 3-phenylpropanal from Wako Pure Chemical Industries, Ltd., after distillation. The checkers used reagent obtained from Lancaster Synthesis without further purification with similar results. 

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