Description white to off-white microcrystalline powder

1. Description
white to off-white microcrystalline powder
https://www.echemi.com/
Basic Attributes
CAS No：2488-15-5
Molecular Formula ：C10H19NO4S
Molecular Mass ：249.33
Exact Mass ：249.103485
PSA ：101 A^2
LogP ：1.6
EINECS ：219-639-3
InChIKeys ：IMUSLIHRIYOHEV-ZETCQYMHSA-N
H-bond Acceptor ：5
H-bond Donor ：2
SP3 ：0.80
RBN ：7
Characteristics
Appearance ：White to off-white Powder
Density ：1.2±0.1 g/cm3
Melting Point ：47-50 °C(lit.)
Bolling Point ：415.5°C at 760 mmHg
Flash Point ：205.1±27.3 °C
Refractive Index ：1.500
Storage Condition ：2-8°C

2. BRN ：1727869
Specific Rotation ：-23 º (c=1.3, methanol)
Safety Information
HS Code ：2930909090
UN No. ：NONH for all modes of transport
WGK_Germany ：3
Risk Code ：20/21/22-36/37/38
Safety Instructions ：24/25-36-26
Dangerous Mark ：Xn
P Code ：P280, P305+P351+P338, P310
Hazard Statements ：H318
Product Usage
Used in biochemical reagents and peptide synthesis.
Production Methods
7.2 g Methionine was dissolved in a mixture of 50 mL water and 50 mL acetonitrile. To this
solution was added2 g NaOH (0.05 mol). The obtained mixture was cooled down to 0°C and

3. then 10.9 g di-t-butyl dicarbonate (0.05 mol)was added. After addition, the mixture was warmed
to room temperature (24-25°C) and reacted for 12 h. Acetonitrilewas removed by distillation.
Potassium carbonate was added to the residue and the pH thereof was adjusted to 12.
Afterextracted with 50 mL dichloromethane twice, the organic layers were discarded. To the
aqueous layer was added 1 Ndilute hydrochloric acid to adjust the pH to 6. After extracted with
50 mL dichloromethane twice, the organic layers werecollected together and washed with 50 mL
saturate solution of sodium chloride and then dried over anhydrous sodiumsulfate, followed by
concentration to obtain a viscous product (11.4 g). The yield was 95percent.1H NMR (500 MHz,
CDCl3) δ 11.62 (br, 1 H), 6.91 (br, 1 H), 4.40 (m. 1H), 2.52 (t, J = 4.8 Hz, 2 H), 2.05 (s, 3H), 1.92∼
2.15(m. 2 H), 1.42 (s, 9 H). Ms (M++1): 250.To the solution of L-methionine (43) (2 g, 13.40 mmol)
in water (12 mL) and acetonitrile (12 mL) was added NaOH (0.804 g, 20.11 mmol) and
boc-anhydride (4.67 mL, 20.11 mmol) at 0 ° C. The reaction mixture was stirred at room
temperature for 12h. After completion, reaction mixture was concentrated under vacuum to
remove acetonitrile and the remaining acqueous layer was diluted with 50 mL water. Aqueous
layer was washed with ethylacetate (2 x 50 mL). The aqueous phase was then adjusted to pH ~
4-5 using aqueous 1N HCl solution and extracted with dichloromethane (4 x 50 mL). Combined
organic extracts were washed with brine (100 mL), dried over Sodium sulphate and evaporated
under reduced pressure to yield (tert-butoxycarbonyl)-L-methionine (44) as a gummy compound
(0.6 g, 8.02 mmol, 60 percent yield) 7.2 g Methionine was dissolved in a mixture of 50 mL water
and 50 mL acetonitrile. To this solution was added 2 g NaOH (0.05 mol). The obtained mixture
was cooled down to 0° C. and then 10.9 g di-t-butyl dicarbonate (0.05 mol) was added. After
addition, the mixture was warmed to room temperature (24-25 ° C.) and reacted for 12 h.
Acetonitrile was removed by distillation. Potassium carbonate was added to the residue and the
pH thereof was adjusted to 12. After extracted with 50 mL dichloromethane twice, the organic
layers were discarded. To the aqueous layer was added 1N dilute hydrochloric acid to adjust the
pH to 6. After extracted with 50 mL dichloromethane twice, the organic layers were collected
together and washed with 50 mL saturate solution of sodium chloride and then dried over
anhydrous sodium sulfate, followed by concentration to obtain a viscous product (11.4 g). The
yield was 95percent.