2-Amino-l-butanol

Nltropropane. The alkanolamines (qv), 2-amino-2-ethyl-l,3-propanediol and 2-amino-l-butanol, are produced by the two-step process described previously. 

Because they are similar, the aLkanolamines often can be used interchangeably. However, cost/perfomiance considerations generally dictate a best choice for specific appHcations. AMPD is manufactured in very low volumes for use as a reagent in certain medical diagnostic tests, although some is used in certain cosmetic products. 2-Ainino-1-butanol is used primarily as a taw material for the synthesis of ethambutol [74-55-5] an antituberculosis dmg. The first step in the synthesis of this dmg is the resolution of AB into its optical isomers because only (i)-2-amino-l-butanol, [5856-62-2] is utilized in this synthesis. 

Amino alcohols can be resolved by a number of pathways including hydrolysis, esterification, and transesterification. For example, hydrolysis of Ai,0-diacet5l-2-amino-l-butanol with PPL followed by recrystallization results in (80a) with 95% ee (108). Hydrolysis of racemic acetates or butyrates of 2-[(aLkoxycarbonyl)amino]-l-aLkanols with PFL gives (R)-alcohol (81) with 95% ee (109). (3)-(81) can be obtained by transesterification of the racemic (81) with ethyl acetate which also serves as the reaction medium (109). 

Gogolewski et al. " combined Pluronic F-68(poly(ethylene-propylene-ethylene oxide) with PCL within the same soft segment. BD or 2-amino-l-butanol was used as the chain extender and HDI as the hard segment. They observed that all the materials calcified and calcification increased with material hydrophilicity. The stmcture and composition of the calcium crystals formed on the materials depended on the PU chemistry. 

Stereospecific nucleophilic substitution in chiral ion—dipole complexes. Chiral molecules can be discriminated in the Cl source of a CIMS instmment by specific ion-molecule reactions induced by chiral reagent gas. This method has been applied with success to distinguish between enantiomeric and diastereomeric forms of menthols ((lR,2S,5R)-(— )-14, (lS,2R,5S)-(+)-14, and (lR,2R,5S)-(—)-14 in Scheme 11) through the nucleophilic displacement of their hydroxyl group by (5)-2-amino-l-butanol Self-protonation of As... 

Fig. 20 MIKE/CID spectra of the substituted m/z228 ions from the enantiomers of menthol ((7/ ,25,5R)-(— )-14 (A) and (75,27 ,55)-(+)-14 (B)) formed under CE(5)-2-amino-l-butanol (As) conditions (the m/z2 0 and mlz90 daugther ions are also produced during unimolecular decomposition of the m/z228 ions) (reprinted from ref. 472, with permission from Elsevier).

Amino-l-butanol and deriv 1 A192—A103 2-nitramino-1-butanol nitrate 1 A192—A193... 

N 16.47%. Col solid, mp 113-113.5°. Was prepd by Elderfield et aI(Refs 2 5) by condensation of 2,4-dinitrochlorobenzene with 2-amino-l-butanol in ale soln and in the presence of NaOH. When nitrated it yields the explosive which may be named ... 

To 27 grams (2.55 mols) of 2-amino-l-butanol was added 100 grams (1.0 mol) of ethylene dichloride. The mixture was heated at reflux and in a few minutes, the exothermic reaction required the removal of exterior heating. After 10 minutes, exterior heating was recommenced for an additional 20 minutes. The hot mixture was then treated with 300 ml of methanol and then cautiously with 84 grams (2.1 mols) of sodium hydroxide in 80 ml of water. 

The precipitated sodium chloride was removed by filtration. The excess 2-amino-l-butanol distilled as light yellow oil at 83° to 87°C/13 mm. The viscous residue distilled at 165° to 170°C/0.6 mm as a light yellow oil which tended to solidify in the air condenser yield, 108 grams. 

FIGURE 7.9 Dutch Resolution of (R,5)-alaninol with (R)-mandelic acid using (R)-, or (5)-2-amino-l-butanol as a family member. 

Even more interesting is the addition of the (.S )-cnantiomcr of 2-amino-1-butanol, which itself forms a salt with (R)-mandelic acid. This salt has almost inhnite solubility. With this additive, the resolution of alaninol with (W)-mandelic acid results in the crystallization of an almost diastereoiso-merically pure salt, without incorporation of 2-amino-l-butanol. On use of this method enantiopure (R)-alaninol can be obtained after an additional recrystallization, without the need to separate the alaninol from the 2-amino-l-butanol. We call this procedure reverse Dutch Resolution, to indicate that the family mix remains in solution. Most likely in this case stereoselective nucleation inhibition plays a role by suppressing the nucleation of the (.S )-alaninol-(A )-mandclic acid diastereoisomer. 

Aminobenzyl alcohol, 21,10 < -Aminobenzyl cyanide, 22, 23, 25 2-Amino-l-butanol, N-alkyl derivative,... 

Syntheses and CD spectra of bisnicotinic acid derivatives with two cyclophane units and (S)-2-amino-l-butanol linker (48) were reported recently. The CD... 

Aliphatic nitro alcohols, conveniently derived by the condensation of nitroparaffins with aldehydes, are reduced to amino alcohols in almost quantitative yields by the action of iron powder and mineral acid. Best results are obtained when an excess of acid is present. The procedure is illustrated by the synthesis of 2-amino-l-butanol (90%). ... 

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