88738-78-7 Usage
Chemical Properties
clear orange to dark orange-brown liquid
Uses
Methyl?P,P-bis(2,2,2-trifluoroethyl)phosphonoacetate can be used:In one of the key synthetic steps for the preparation of?trans-hydrindanes and (R)-(+)-umbelactone.To prepare a cis-olefinic ester derivative by Still–Gennari olefination of an aldehyde derivative using 18-crown ether and potassium bis(trimethylsilyl)amide (KHMDS).In the synthesis of (?)-(6S,2′S)-epi?cryptocaryalactone.
Synthesis
The synthesis method of Bis(2,2,2-trifluoroethyl) (Methoxycarbonylmethyl) phosphonate is as follows: To a stirred solution of dried 18-crown-6 (4.53 g, 17.14 mmol), THF (20 mL),
and Bis(2,2,2-trifluoroethyl) Phosphite (0.70 mL, 1.29 mmol), was added KHMDS (9.0 mL, 4.50 mmol, 0.5M in
toluene) by syringe in a dropwise manner at -78 ℃. After 15 min, methyl chloroacetate
(0.30 mL, 3.41 mmol) was added and the reaction mixture was allowed to stir for 4 hr at
room temperature. The reaction mixture was diluted with EtOAc (20 mL) and then
quenched with sat. ammonium chloride (50 mL). The aqueous layer was extracted with
EtOAc (3 x 30 mL). The combined organic extracts were dried under anhydrous
magnesium sulfate. Following filtration, the solvents were removed in vacuo. The crude
product was then purified by flash column chromatography (33% EtOAc in hexanes, Rf =
0.22 in 33% EtOAc in hexanes) yielding Bis(2,2,2-trifluoroethyl) (Methoxycarbonylmethyl)phosphonate (766 mg, 2.41 mmol, 70.3%)
as a yellow syrup.
Check Digit Verification of cas no
The CAS Registry Mumber 88738-78-7 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 8,8,7,3 and 8 respectively; the second part has 2 digits, 7 and 8 respectively.
Calculate Digit Verification of CAS Registry Number 88738-78:
(7*8)+(6*8)+(5*7)+(4*3)+(3*8)+(2*7)+(1*8)=197
197 % 10 = 7
So 88738-78-7 is a valid CAS Registry Number.
InChI:InChI=1/C21H11F5O3/c22-15-16(23)18(25)20(19(26)17(15)24)29-21(27)28-9-14-12-7-3-1-5-10(12)11-6-2-4-8-13(11)14/h1-8,14H,9H2
88738-78-7Relevant articles and documents
A Straightforward, Purification-Free Procedure for the Synthesis of Ando and Still-Gennari Type Phosphonates
Janicki, Ignacy,Kie?basiński, Piotr
, p. 378 - 382 (2021/10/21)
Z-Selective Still-Gennari and Ando modifications of the typically E-selective Horner-Wadsworth-Emmons reaction are highly valuable synthetic tools in organic chemistry. These procedures are based on application of bis(2,2,2-trifluoroethyl) phosphonates or diaryl phosphonates, respectively, for the olefination of carbonyl groups. In our research, we present an improved, straightforward, purificationfree procedure for the synthesis of these reagents. The key step of our procedure is the reaction of phosphonic dichlorides with the appropriate sodium alkoxides, which results in 52-97% isolated yields of the desired products on a gram scale. The whole three-step process is performed in one pot. Most importantly, the product is obtained in over 95% purity after simple extraction, avoiding column chromatography and distillation. Moreover, we present the synthesis of a novel Still-Gennari type reagent, bis(1,1,1,3,3,3-hexafluoroisopropyl) phosphonates, which may exhibit improved Z-selectivity in Still-Gennari olefinations.
Stereoselective Synthesis of the Benzodihydropentalene Core of the Fijiolides
Kurzawa, Timon,Harms, Klaus,Koert, Ulrich
supporting information, p. 1388 - 1391 (2018/03/09)
An efficient stereoselective synthesis of the enantiomer of the benzodihydropentalene core of fijiolides A and B has been achieved. The asymmetric conjugate addition of styrylboronic acid to an indenone produced the first stereocenter. Ring C was installe
DIRECT SYNTHESIS OF Z-UNSATURATED ESTERS. A USEFUL MODIFICATION OF THE HORNER-EMMONS OLEFINATION.
Still, W. Clark,Gennari, Cesare
, p. 4405 - 4408 (2007/10/02)
New phosphonoester reagents and reaction conditions are described which yield Z-alpha,beta-unsaturated esters stereoselectively and in high yield from aliphatic and aromatic aldehydes.
