Реакция #1117706

Уравнение реакции

ammonium chloride

N-tert-butoxycarbonyl-L-leucinal

1-methyl-1,2,4-triazole

n-butyllithium

→

(S)2-(tert-butoxycarbonyl)amino-4-methyl-(R)1-(1-methyl-1H-1,2,4-triazol-5 -yl)pentan-1-ol

Растворители

tetrahydrofuran

tetrahydrofuran

Условия реакции

Обработка

1. 1
   workup.STIRRINGThe mixture was stirred 1/2 hour each at -75° C.
2. 2
   Концентрированиеconcentrated
3. 3
   ПромывкаThe residue in 100 ml of ethyl acetate was washed with 50 ml of each of water, 2N citric acid, 1M sodium bicarbonate and brine
4. 4
   Другоеdried
5. 5
   ФильтрацияThe solution was filtered
6. 6
   Концентрированиеconcentrated
7. 7
   Другоеto give 8.41 g (88%) f a colorless oil which
8. 8
   Другоеpartly crystallized
9. 9
   ДругоеTwo recrystallization from iso-propyl acetate

Методика

To a solution of 5.3 g of 1-methyl-1,2,4-triazole in 100 ml of tetrahydrofuran under nitrogen at -75° C. was added via syringe 25.6 ml of n-butyllithium. The solution was stirred 1.5 hour at -75° C. and then 6.9 g of N-tert-butoxycarbonyl-L-leucinal in 25 ml of tetrahydrofuran at -75° C. was added. The mixture was stirred 1/2 hour each at -75° C. and at -23° C. the mixture was treated with 10 ml of saturated ammonium chloride and concentrated. The residue in 100 ml of ethyl acetate was washed with 50 ml of each of water, 2N citric acid, 1M sodium bicarbonate and brine and dried. The solution was filtered and concentrated to give 8.41 g (88%) f a colorless oil which partly crystallized. Two recrystallization from iso-propyl acetate afforded 1.85 of (S)2-(tert-butoxycarbonyl)amino-4-methyl-(R)1-(1-methyl-1H-1,2,4-triazol-5 -yl)pentan-1-ol, mp 144°-145° C. [α]D26 -26±1°(c, 1.1, MeOH).

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