ChemicalBook CAS DataBase List Methyl N-Boc-L-proline-3-ene

Methyl N-Boc-L-proline-3-ene synthesis

7synthesis methods

Product Name:Methyl N-Boc-L-proline-3-ene
CAS Number:74844-93-2
Molecular formula:C11H17NO4
Molecular Weight:227.26

51154-06-4 Synthesis

51154-06-4
133 suppliers
$12.00/100mg

18107-18-1
209 suppliers
$33.00/5g

74844-93-2
104 suppliers
$34.00/100mg

Yield:74844-93-2 100%

Reaction Conditions:

Stage #1: (S)-2,5-dihydropyrrole-1,2-dicarboxylic acid 1-tert-butyl ester;diazomethyl-trimethyl-silane in methanol;hexane;toluene at 0; for 0.75 h;
Stage #2: with acetic acid in methanol;hexane;toluene;Product distribution / selectivity;

Steps:

2.a

(Trimethylsilyl)diazomethane (2.0 M solution in hexane, 200 mL, 400 mmol) was added dropwise over 15 minutes to a stirred mixture of toluene (600 mL), methanol (100 mL) and (S)-Boc-3,4-dehydroproline (1) (ex. Bachem, 50 g, 234.4 mmol) whilst EPO cooling with iced-water under an atmosphere of argon. The yellow solution was stirred for 30 minutes then acetic acid ~ 15 mL was added to obtain a colourless solution. The solvents were removed in vacuo to leave ester (2) (56.58 g, >100 % yield) as a pale yellow oil which was used without further purification. TLC (single UV spot, Rf= 0.10, heptane : ethyl acetate 1 : 1); analytical HPLC single main peak, R_t - 14.26 min., HPLC-MS 128.2 [M + 2H - Bocf, 172.1 [M + 2H - Bu]⁺, 477.3 [2M + Na]⁺.

References:

WO2007/17698,2007,A1 Location in patent:Page/Page column 30-31

74844-91-0 Synthesis