L -Valine.hydrochloride

C25H30N2O3 137863-90-2) see Valsartan methyl L-valinate hydrochloride (C(jHi4ClN02 6306-52-1) see Valsartan methyl vinyl ketone... 

DLSERN11. D,L-Serine (neutron study) (C3H7N03). Frey MN, Lehmann MS, Koetzle TF, Hamilton WC (1973) Acta Crystallogr, Sect B 29 876 DLTYRS. D,L-iyrosine (CgHnNO. Mostad A, Romming C (1973) Acta Chem Scand 27 401 DLVALC. D,L-Valine hydrochloride (C5H12NO, Cl-). Di Blasio B, Napolitano G, Pedone C... 

VALEHC10. L-Valine hydrochloride (C5H12N02+, Cl"). Ando O, Ashida T, Sasada Y, Kakudo M (1967) Acta Crystallogr 23 172... 

VALEHC11. LrValine hydrochloride (neutron study) (CjH NO, Cl-). Koetzle TF, Golic L, Lehmann MS, Verbist JJ, Hamilton WC (1974) J Chem Phys 60 4690 VALHCL10. L-Valine hydrochloride monohydrate (CsH NO, Cl-, H20). Rao ST (1969) Z Kristallogr 128 339... 

Gervais et al. also studied selected amino acid hydrochlorides, using i4n, i7q 35( j SSNMR spectroscopy in 2005. EFG and isotropic chemical shift data were reported for glycine hydrochloride, L-valine hydrochloride and... 

The compounds investigated were the amino acids L-isoleucine, L-leucine, L-valine, and L-a-amino butyric acid. These compounds have similar molecular structures, as shown in Figure 2, and will be referred to throughout the present work as L-Ile, L-Leu, L-Val, and L-a-ABA. Where there is little likelihood of confusion, the designation L- will be omitted. Operations examined included crystallization of He through the addition of hydrochloric acid and through cooling. Under acidic conditions He crystallizes as a hydrochloride salt while in the vicinity of the isoelectric point (pH 5.2) it crystallizes as the neutral zwitterionic... 

L)-Valine methyl ester hydrochloride 2 -Cyanobiphenyl-4-carbaldehyde Sodium cyanoborohydride... 

L-Valine methyl ester hydrochloride Valine, methyl ester, hydrochloride, L-(8) L-Valine, methyl ester, hydrochloride (9) (6306-52-1)... 

The Step 4 product (14.4 mmol) was dissolved in 160 ml THF and treated with 5 A molecular sieves (16 g) and L-valine methyl ester hydrochloride (28.8 mmol), then stirred 30 minutes at ambient temperature. The solution was further treated with the dropwise addition of sodium cyanoborohydride (14.4 mmol) in 18 ml methyl alcohol at 0—5°C and the mixture stirred overnight at ambient temperature. The solution was concentrated, the residue purified by chromatography using EtOAc/n-heptane, 1 2, and 4.41 g of product isolated as an amorphous solid... 

The starting dihydrooxazoles 1 are readily prepared by condensing an amino alcohol with an appropriate imidate hydrochloride or the free carboxylic acid. A-Allylation of 1 with ally] tosylate has proved to be superior to other procedures. Neutralization of the dihydrooxazolium salt 2 and rearrangement of 3 are conveniently performed as a one-pot operation. The potential of this method has been demonstrated by the enamioselective synthesis of (- )-(/ )-2-methylpent-4-enoic acid on the basis of L-valine. 

CIN2O3, L-Glutamine hydrochloride, 38B, 483 1CIN2O6, Cucurbitine perchlorate, 30B, 212 1NO2, DL-Valine, 34B, 269 1NO2, L-Valine, 35B, 310... 

K2G03-soln. added at ca. 10° to a soln. of L-valine ferf-butyl ester hydrochloride in chloroform, then dicarbobenzoxycystinyl dichloride added with stirring, which is continued for 0.5 hr. dicarbobenzoxy-L-cystinylbis-L-valine ferf-butyl ester (Y 77-82%) treated with a 2 M soln. of HBr in glacial acetic acid, allowed to stand 1 hr. at room temp, with occasional swirling, and the resulting dihydrobromide treated with LiOH in water L-cystinylbis-L-valine... 

High stereoselectivities (94-100 %) are attained in the reduction of aromatic ketones by use of a new chiral borane complex with (S)-2-amino-3-methyl-l,l-diphenylbutan-l-ol,(S-68) readily prepared in two steps from (S)-valine, in an experimentally convenient procedure961. (S)-Valine methyl ester hydrochloride was converted with excess of phenylmagnesium bromide into (S-68). The same treatment of (R)-valine gave (R-68). In a typical asymmetric reduction the reagent, prepared from (S-68) and borane, and the ketone (69) in tetrahydrofuran were kept at 30 °C for some hours. The corresponding alcohols were obtained in high optical purity. (S-68) could be recovered to more than 80% without racemization 96). 

To a 5 L 3-neck round bottom flask was added the crude carbonylbenzyloxy-3-aminopropanal (115 g, 0.555 mol) followed by addition of water (400 mL) and methanol (1600 mL). The reaction mixture was maintained at 25°C throughout the course of the reaction. After the solution became homogeneous. (S)-Valine methyl ester hydrochloride (90.2 g, 0.538 mol) was added in one portion followed by rapid addition of sodium acetate trihydrate (151 g, 1.11 mol) and sodium cycanoborohydride (73.2 g, 1.17 mol). The reaction mixture was allowed to stir at room temperature for 0.5 hour and was concentrated in vacuo. To this solution, saturated aq sodium bicarbonate (400 mL) was added and the mixture was extracted with isopropyl acetate (1 L). The organic layer was washed with water, dried over sodium sulfate, and concentrated to yield 150 g of crude product, which was dissolved in isopropyl acetate (300 mL) and heptane (2400 mL). Dry HCI was bubbled in and an oily solid precipitated out of solution. The liquid was decanted away from and the solid was dissolved in dichloromethane (3 L). The solution was washed with water (600 mL) and saturated aq sodium bicarbonate (600 mL) and dried over sodium sulfate. It was concentrated in vacuo to yield 105 g (59%) of N-(N-(benzyloxycarbonyl-3-amino)-propyl)valine methyl ester as a light yellow oil. 

In 1981, Hirao and others reported that the chiral borane-amine complex 25a, derived from (S)-prolinol and 1 equivalent of BH3 THF, enantioselec-tively reduced propiophenone to afford (R )-l -phenyl-1 -propanol (26) in 44% ee9 (Scheme 4.3h). The chiral complex 25b was even better than 25a, affording the same secondary alcohol in 60% ee. Two years after the initial disclosure, Hirao et al. uncovered a new catalyst system that improved the previous experimental conditions dramatically10 (Scheme 4.3i). When the chiral aminoalcohol 27, prepared from (S)-valine methyl ester hydrochloride and phenylmagnesium bromide, was used along with 2 equivalents of BH3 THF, the enantioselectivity of the alcohol 26 jumped to 94% ee. In addition, the reaction time was shortened to 2 hours. 

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