تفاعل #429293

معادلة التفاعل

tributyltin hydride

2-decanoylamino-pentanedioic acid

2-Decanoylamino-pentanedioic acid 5-allyl ester 1-benzyl ester

→

8

المردود 80.0%

2-Decanoylamino-pentanedioic acid 1-benzyl ester

المردود 80.0%

المذيبات

CH2Cl2

ظروف التفاعل

المعالجة

1. 1
   أخرىthe reaction mixture was quenched with 10 mL of a 10% HCl solution
2. 2
   تجفيفthe organic layer dried (Na2SO4)
3. 3
   تركيزconcentrated in vacuo
4. 4
   أخرىchromatographed on SiO2 (Hexanes/EtOAc, 9:1)

الإجراء التجريبي

Pd(O)-catalyzed deprotection of the allyl ester proceeded as follows to yield 2-Decanoylamino-pentanedioic acid 1-benzyl ester (8). To a solution of 752 mg (1.74 mmol) of 2-decanoylamino-pentanedioic acid 7 in 10 mL of CH2Cl2 was added 100 mg (0.087 mmol) of tetrakistri-phenylphosphine Pd(O) followed by 0.52 mL (1.9 mmol) of tributyltin hydride. After 15 min, the reaction mixture was quenched with 10 mL of a 10% HCl solution. The aqueous layer was reextracted with 15 mL of CH2Cl2 and the organic layer dried (Na2SO4), concentrated in vacuo, and chromatographed on SiO2 (Hexanes/EtOAc, 9:1) to provide 545 mg (79.9%) of 8 as a thick oil: [α]D +2.8° (c 1.2, CHCl3, 21° C.); IR (neat) 3351, 3064, 2995, 2852, 1738, 1712, 1657, 1536, 1454, 1380, 1364, 1265, 1209, 1183, 1121, 739 cm-1 ; 1H NMR δ 10.9-10.7 (bs, 1 H), 7.22 (s, 5 H), 6.58 (d, 1 H, J=7.8 Hz), 5.09 (s, 2 H), 4.63 (dd, 1 H, J=8.1, 12.9 Hz), 2.4-2.25 (m, 2 H), 2.2-2.1 (m, 3 H), 2.0-1.9 (m, 1 H), (m, 6 H), 1.53 (t, 2 H, J=6.6 Hz), 1.19 (bs, 12 H), 0.81 (t. 3 H, J=6.0 Hz); 13C NMR δ 176.9, 174.0, 171.8, 134.9, 128.5, 128.4, 128.1, 67.3, 51.4, 36.2, 31.7, 29.9, 29.3, 29.2, 29.1, 27.0, 25.5, 22.5, 14.0; MS (El) m/z (relative intensity) 391 (54), 373 (62), 279 (13), 256 (19), 178 (27), 178 (23), 155 (13), 146 (6), 130 (7), 102 (100); HRMS (El) m/z calculated for C22H33NO5 :391.2358, found: 391.2350.

المصدر