物质信息
ID:717858
名称和标识
IUPAC标准名
2,2-dimethyl-1,3-dioxane-4,6-dione
IUPAC传统名
meldrum's acid
别名
2,2-Dimethyl-1,3-dioxane-4,6-dioneMeldrum's Acid丙二酸亚异丙酯Isopropylidene malonate
化合物性质
理化性质
熔点
92-96°C
安全信息
GHS危险品标识
急性毒性（口服，皮肤接触，吸入），类别4
皮肤刺激，类别2
眼刺激，类别2
皮肤过敏，类别1
特定目标器官毒性 -一次接触，类别3
危险公开号
36/37/38
GHS危险声明
H315-H319-H335
欧盟危险性物质标志
刺激性 (Xi)TSCA收录
是
GHS警示性声明
P261-P305+P351+P338-P302+P352-P321-P405-P501A
安全公开号
26-37
RTECS编号
JH0800000
产品相关信息
纯度
98%
描述信息
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分子图谱
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参考文献
• With an aryl aldehyde in the presence of triethylamine and formic acid at ambient temperature, in situ reduction to the arylmethyl Meldrum's acid occurs, whereas at 70-80oC, the 3-arylpropionic acid is obtained: Synth. Commun., 25, 3067 (1995).
• Condensation with lactim ethers, catalyzed by Nickel(II) 2,4-pentanedionate, 18811, with alcoholysis of the resulting enamino Meldrum's acids, gives of cyclic ?-enamino esters, useful as alkaloid precursors: J. Org. Chem., 43, 4662 (1978); for an example, see: Org. Synth. Coll., 8, 263 (1993).
• Malonate ester which is an unusually strong acid (pKa = 9.97) in comparison with, e.g. Diethyl malonate, A15468: J. Am. Chem. Soc., 70, 3426 (1948). The mild conditions required for alkylation, acylation, etc. and the ease with which the products undergo alcoholysis or hydrolysis-decarboxylation make Meldrum's acid a valuable and versatile synthetic intermediate. Reviews: Chem. Soc. Rev., 7, 345 (1978); Heterocycles, 32, 529 (1991); Synlett, 1649 (2004).
• C-Acylation with acyl chlorides occurs in the presence of 2 equivalents of pyridine in high yield. Alcoholysis of the product provides a good route to ?-keto esters: J. Org. Chem., 43, 2087 (1978); Org. Synth. Coll.,7, 359 (1988), also obtainable by reaction of the Na salt with acid anhydrides in DMF: Synthesis, 451 (1982). Alternatively, mild hydrolysis and decarboxylation of the intermediate acyl Meldrum's acid gives the methyl ketone, providing an alternative to organometallic methods for conversion of acyl chlorides to methyl ketones: Synth. Commun., 10, 221 (1980):
• Knoevenagel condensation with aldehydes gives ylidene derivatives which are solvolyzed by alcohols to give monoesters of alkylidene or arylidene malonic acids: J. Am. Chem. Soc., 74, 5897 (1952). For diastereoselective condensation with citronellal, followed by intramolecular Diels-Alder reaction, see: Org. Synth. Coll., 8, 353 (1993). With formaldehyde in pyridine gives the stable pyridinium methylide which, on treatment with acid, generates the useful reactive Michael acceptor and dienophile, methylene Meldrum's acid: Synthesis, 215 (1996).
• See also: Org. Synth., 77, 114 (1999).
• For phase-transfer alkylation using K2CO3 as base, see: Synthesis, 452 (1982); Bull. Soc. Chim. Belg., 104, 643 (1995). Phase-transfer addition to Michael acceptors also occurs: Synthesis, 224 (1984). Mitsunobu dialkylation with an alcohol and DIAD/Ph3P is also possible: J. Org. Chem., 62, 1617 (1997).