Diethyl ethylidenemalonate

The phosphine-containing ruthenium dihydride dendrimer 33 was found to be an active catalyst for the diastereoselective Michael addition of ethyl cyanoacetate to diethyl ethylidenemalonate in THF (Scheme 12). The dendritic catalyst showed an activity and selectivity similar to those of the reference compound RuH2(PPh3)4 (100% conversion after 24 h and a diastereoselectivity of 7/3) (40). The dendritic catalyst was recycled twice by precipitation with diethyl ether without loss of activity or selectivity. Complex 34 showed similar activity and recoverability over three runs like that of complex 33. 

DIETHYL ETHYLIDENEMALONATE (Malonic acid, ethylidene-, diethyl ester)... 

The reflux condenser is replaced by a Claisen distillation head, and the reaction mixture is distilled until the temperature of the vapor reaches 140°. The residue is transferred to a smaller flask and fractionated through a 30-cm. column packed with glass helices. A low-boiling fraction containing ethylidene diacetate and diethyl malonate is collected first, followed by 79-89.5 g. (68-77%) of diethyl ethylidenemalonate b.p. 102-106°/10 mm. %>5 1.4394 (Note 1). 

Diethyl ethylidenemalonate has been prepared by heating acetaldehyde, diethyl malonate, and acetic anhydride 2 3 by heating the same reagents plus zinc chloride 4 by treating acetaldehyde and diethyl malonate with sodium ethoxide or piperidine 6 and by heating diethyl malonate, ethylidene bromide, and ethanolic sodium ethoxide.6... 

Diethyl ethylidenemalonate, 32, 54 Diethyl ethylphosphonate, 31, 34 Diethyl fumarate, 30, 46 Diethyl heptanoylsuccinate, 34, 51 Diethyl j-hexahydrophthalate,... 

Crotyltriisopropoxytitanium (l).6 The reaction of diethyl ethylidenemalonate (2) with 1 produces the anti-adduct (3) as the major product. Comparable selectivity is shown by B-crotyl-9-borabicyclo[3.3.1]nonane, but crotylzirconium or -magnesium reagents show less stereoselectivity. 

Diethyl ethylidenemalonate, CH3CH=C(COOC2H,)2 (1). Mol. wt. 186.21, b.p. 115-118V17 mtn. Preparation. Supplier Aldrich, Fluka. 

Similar oxidants are used for epoxidation of esters of unsaturated carboxylic acids. Methyl oleate is oxidized with peroxybenzoic acid [295] or peroxylauric acid [174] to methyl 9,10-epoxystearate acid in respective yields of 67 and 76%. Alkaline 50% hydrogen peroxide in methanolic solution transforms diethyl ethylidenemalonate at pH 8.5-9.0 and at 35-40 C over a period of 1 h into ethyl 2-ethoxycarbonyl-2,3-epoxybutyrate in 82% yield [145], A somewhat exotic oxidizing agent, dimethyldioxirane, converts ethyl tra/u-cinnamate into ethyl 2,3-epoxyhydrocinnamate in 63% isolated yield [210]. 

The 1,4-conjugate Se addition of allylic stannanes is a successful variant of the Michael reaction, particularly in examples which provide stable coordination complexes with strong Lewis acids. For the most part, simple allylstannanes have been utilized in these reactions. The addition of ( )-2-butenyltri-n-bntylstannane to diethyl ethylidenemalonate (173) proceeds in modest yield with high stereoselectivity to give the anti-isomer 174 via the antiperiplanar arrangement 175 (Scheme 5.2.37).53... 

The gross structures of the three compounds were confirmed as correctly represented by CVI, CVII, and CVIII by the unequivocal synthesis of ( )-pseudoheliotridane by Leonard and Felley (151, 152). The synthesis involved three steps (a) the Michael addition of nitro-methane to ethyl crotonate or diethyl ethylidenemalonate (CIX) ... 

---