ChemicalBook CAS DataBase List 1,3-Dioxolane, 4-ethynyl-2,2-dimethyl-, (R)- (9CI)

1,3-Dioxolane, 4-ethynyl-2,2-dimethyl-, (R)- (9CI) synthesis

5synthesis methods

Product Name:1,3-Dioxolane, 4-ethynyl-2,2-dimethyl-, (R)- (9CI)
CAS Number:186521-82-4
Molecular formula:C7H10O2
Molecular Weight:126.15

22323-80-4 Synthesis

22323-80-4
140 suppliers
$71.50/5g

1,3-Dioxolane, 4-ethynyl-2,2-dimethyl-, (R)- (9CI)

186521-82-4
7 suppliers
inquiry

Yield:186521-82-4 70%

Reaction Conditions:

with dimethyl 1-(1-diazo-2-oxopropyl)phosphonate;potassium carbonate in methanol at 0 - 20; for 12.5 h;

Steps:

17

Example 17 (R)-(-)-4-Ethynyl-2,2-dimethyl-1 ,3-dioxolaneThe solution of L-glyceraldehyde acetonide prepared from ascorbic acid (Ch. Hubschwerlin, Synthesis 1986. 962-964) (1.03 g, 7.90 mmol) and Bestmann-Ohira reagent (2.42 g, 12.6 mmol) in methanol (50 ml) is cooled to 0⁰C. Potassium carbonate (2.33 g, 16.8 mmol) is then added portionwise during 30 min, followed by stirring the reaction mixture at room temperature for 12 hours. Then a saturated solution of NH₄CI (50 ml) is added and the resulting solution is extracted with pentane (2 x 250 ml). The combined organic layers are dried over magnesium sulfate and after removal of the solvent the residue is subjected to silica gel chromatography (pentane/diethyl ether 10:1 ) to afford 0.7 g (70%) of (R)-(-)-4- ethynyl-2 ,2-dimethyl-1 ,3-dioxolane in the form of yellow oil.[α]_D -40° (c 1.2, CH₂CI₂). IR (film): 2121 cm^"1.¹H NMR (200 MHz, CDCI₃), δ: 4.67 (1 H, m), 4.15 (1 H, dd, J 8.1. 6.4 Hz), 3.91 (1 H, dd, J 8.1. 6.2 Hz), 2.47 (1 H, d, J 2.3 Hz), 1.47 (3H, s, Me), 1.35 (3H, s, Me).

References:

WO2010/97350,2010,A1 Location in patent:Page/Page column 29-30