2- Phenyl-l-propanol

The catalyst is inactive for the hydrogenation of the (isolated) benzoie nucleus and so may be used for the hydrogenation of aromatic compounds containing aldehyde, keto, carbalkoxy or amide groups to the corresponding alcohols, amines, etc., e.g., ethyl benzoate to benzyl alcohol methyl p-toluate to p-methylbenzyl alcohol ethyl cinnamate to 3-phenyl-l-propanol. 

Phenyl-l-propanol [Reduction of a Carboxylic Acid to an Alcohol].280... 

FIGURE 1.54 HPLC chromatogram of 2-amino-3-phenyl-l-propanol generated by cleavage of its t-BOC derivative with trifluoroacetic acid and clean-up on strata-X-C. 

The crude material was purified by flash chromatography over silica gel (150 g) using ethyl acetate-u-hexane (1 9) as eluent to give (25, 5[Pg.75]

Lithium aluminum hydride reduction furnishes racemic 2-alkyl-l-alkanols in good yields13. Thus, from alkylation of 1,3-diacylimidazolidinone 1 with benzyl bromide followed by reduction, a 73% yield of ra< -2-methyl-3-phenyl-l-propanol is obtained. When this sequence is carried out with (R,R)-1 as starting material, (S )-2-methyl-3-phenyl-l-propanol is obtained in 93% ee [a]D -10.2 (c = 1.1, C6H6) 13. 

The Friedel-Crafts alkylation of aromatic compounds by oxetanes in the presence of aluminum chloride is mechanistically similar to the solvolyses above, since the first step is electrophilic attack on the ring oxygen by aluminum chloride, followed by a nucleophilic attack on an a-carbon atom by the aromatic compound present. The reaction of 2-methyloxetane and 2-phenyloxetane with benzene, toluene and mesitylene gave 3-aryl-3 -methyl-1-propanols and 3-aryl-3-phenyl-l-propanols as the main products and in good yields (equation 27). Minor amounts of 3-chloro-l-butanol and 4-chloro-2-butanol are formed as by-products from 2-methyloxetane, and of 3-phenyl-l-propanol from 2-phenyloxetane (73ACS3944). 

The bromide could be prepared from 3-phenyl-l-propanol ( 59/kg). The unsaturated aldehyde O can be made by oxidation (Cr03.py) of 4-penten-l-ol ( 41.80/10 g). A cheaper way is to make ethyl 4-pentenoate from ethyl acetate ( 15/gal) and allyl bromide ( 19/100 g) and reduce it to the aldehyde O with DIB AH ( 19/ 0.1 mol). 

Thus a synthesis of M based on this retrosynthetic analysis would start with edryl acetate, allyl bromide, and 3-phenyl-l-propanol. 

Benzyl alcohol Benzyl bromide 3-Phenyl-l-propanol... 

Phenyl-l-propanol 136.19/C9H120/ colorless, slightly viscous s—most fixed oils, 1 mL in 1... 

A mixture consisting of 3-amino-3-phenyl-l-propanol (6.6 mmol), 4-chloro-2-fluorobenzonitrile (6.4 mmol) and 1.2 ml /V,/V-diisopropylcthylamine was heated 5 hours at 140°C then cooled. The material was purified by chromatography with... 

FIGURE 13.3. Reaction profiles for DBSA-catalysed reactions in water. Closed circle esterification of lauric acid with 3-phenyl-l-propanol (1 1). Open square hydrolysis of 3-phenyl-1-propyl lauratc. 

Conditions lauric acid/3-phenyl-l-propanol = 1 1, at 40°C in water (3 ml/0.5 mmol of lauric acid). 

Heterogeneous catalysis The heterogeneous catalyst, either the finely dispersed metal itself or the metal adsorbed onto a support, remains in a separate phase during the course of reaction. Examples of hydrogenation of alkenes given below include reduction of oleic acid (6.1) with H2 and Pd-C to octadecanoic acid (6.2) and cinnamyl alcohol (6.3) and Raney nickel in ethanol to 3-phenyl-l-propanol (6.4). 

SYNS 3-BENZENEPROPANOL FEMA No. 2885 HYDROCINNAAfYL ALCOHOL (3-HYDROXYPROP-YL)BENZENED 7-PHENYLPROPANOL 3-PHENYL-PROPANOL 3-PHENYL-l-PROPANOL(FCC) PHENYLPROPYL ALCOHOL y-PHENWEPROPYL ALCOHOL S-PHENYLPROPYT ALCOHOL... 

SYNS FEMANo. 2890 3-PHENYL-l-PROPANOL ACETATE PHENYLPROPYL ACETATE 3-PHENYLPROPYL ACETATE (FCQ 3-PHENYL-1-PROPYL ACETATE... 

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