31952-14-4

Upstream product

• 3709-27-1 5-benzyl-2,2-dimethyl-1,3-dioxane-4,6-dione 
• 100-51-6 benzyl alcohol 
• 2033-24-1 cycl-isopropylidene malonate 
• 100-39-0 benzyl bromide 
• 2759-28-6 1-phenylmethylpiperazine 
• 1214-54-6 5-benzylidene Meldrum's acid 
• 100-44-7 benzyl chloride 
• 100-52-7 benzaldehyde 

Downstream Products

• 1146212-24-9 C₁₇H₁₆⁽²⁾H₂O₃ 
• 1146212-14-7 2,2-dibenzyl-3-hydroxy-propionic acid 
• 618-68-8 2-benzyl-3-phenylpropanoic acid 
• 16307-30-5 2-benzyl-1-indanone 
• 4372-32-1 dibenzylmalonic acid 

Relevant academic research and scientific papers

Organic reactions in ionic liquids: Alkylation of Meldrum's acid

The room temperature ionic liquid N-butylpyridinium tetrafluoroborate, [bpy]BF4 is used as a "green" recyclable alternative to classical molecular solvents for the alkylation of Meldrum's acid.

C-alkylation of Meldrum's acid using triphenyl phosphine and N-bromosuccinimide

A simple and efficient method for the C-alkylation of Meldrum's acid by alcohol using triphenyl phosphine and N-bromosuccinimide is described. Primary alcohols yielded bis-alkylated Meldrum's acid whereas secondary alcohols yielded mono-alkylated Meldrum's acid.

Activity of: N, N ′-dialkyl-2-trifluoromethylthioimidazolium salts as phase-transfer catalyst for the alkylation of active methylene compounds

We herein report the synthesis of N,N′-dialkyl-2-trifluoromethylthioimidazolium salts from thioureas using nucleophilic trifluoromethylating reagents. The activity of imidazolium salts as phase-transfer catalysts under solid-liquid phase conditions was in

Di-p-nitrobenzyl azodicarboxylate (DNAD): An alternative azo-reagent for the Mitsunobu reaction

Di-p-nitrobenzyl azodicarboxylate is prepared in 83.6% yield in two steps as a bright yellow solid, which can be used as an azo-reagent in the Mitsunobu reaction. When a chiral secondary alcohol was used, sufficient configurational inversion of alcohol occurred under Mitsunobu conditions. That the hydrazine produced from DNAD is semisoluble in some solvents such as THF and CH 2Cl2 makes it separated easily from the reaction mixture just via filtration. Then the recovered hydrazine compound can be re-exposed to oxidant to produce DNAD. Because DNAD is more stable than DIAD at ambient temperatures and allows easy separation, it is a good alternative azo-reagent for the Mitsunobu reaction.

Reactions of acetylenic acid esters with piperazine derivatives

Hg(II)-EDTA-dehydrogenation of benzylpiperazine (5) in 50% ethanol with addition of diethyl acetylenedicarboxylate (2) to a minor extent gives rise to (piperazine-1,4-diyl)-bis(maleate) (9), which is inert to Hg(II)-EDTA and results in quantitative yield when Hg(II)-EDTA is omitted. 4-Benzylpiperazin-1- yl)-monomaleate (8) reacts with 2 in various solvents by addition of water with dealkylation and formation of 9. CH-acidic compounds may also be used as proton donors. Analogous reactions, although with minor yields, occur with the propiolates 11 and 12. 1-Substituted piperazines with benzyl, methine or allylic groups (5-5c, 27d-g, and 27h) react readily with acetylenedicarboxylic acid esters to give compounds of type 9, whereas benzhydryl, aromatic and most of the unbranched aliphatic substituents are not replaced. The reactivity of 1,4-disubstituted piperazines corresponds largely to the behaviour of the substituents in the monosubstituted derivatives.

Some unusual reactions of Meldrum's acid. Synthesis of cinnamic acids, coumarins and 2-benzyl-1-indanone

The use of Meldrum's acid (1) in the synthesis of the substituted cinnamic acid 3 and malonic acid 4, the coumarins 8 and 9, and of 2-benzyl-1-indanone (13), is reported. The structure of benzylidene benzalmalonate is corrected to 14.

Meldrum's acids as acylating agents in the catalytic intramolecular Friedel-Crafts reaction

(Chemical Equation Presented) The intramolecular Friedel-Crafts acylation of aromatics with Meldrum's acid derivatives catalyzed by metal trifluoromethanesulfonates is reported. Meldrum's acids are easily prepared, functionalized, handled, and purified. The synthesis of polysubstituted 1-indanones from benzyl Meldrum's acids was investigated thoroughly, and it was shown that a variety of catalysts were effective, while accommodating a diversity of functional groups under mild conditions. The scope, limitations, and functional group tolerance (terminal alkene and alkyne, ketal, dialkyl ether, dialkyl thioether, aryl methyl ether, aryl TIPS and TBDPS ethers, nitrile- and nitro-substituted aryls, alkyl and aryl halides) for a variety of 5-benzyl (enolizable Meldrum's acids) and 5-benzyl-5-substituted Meldrum's acids (quaternized Meldrum's acids), forming 1-indanones and 2-substituted-1- indanones, respectively, are delineated. This method was further applied to the synthesis of 1-tetralones, 1-benzosuberones, and the potent acetylcholinesterase inhibitor donepezil. Rate of cyclization as a function of ring size was established for various benzocyclic ketones via competition experiments: 1-tetralones form faster than both 1-indanones and 1-benzosuberones, and 1-benzosuberones cyclize faster than 1-indanones.

One Pot Synthesis of Monoalkylated and Mixed, Dialkylated Meldrum's Acid Derivatives

A simple one pot method, involving sequential Knoevenagel condensation of Meldrum's acid with aromatic aldehydes, conjugate reduction of ylidene Meldrum's acid using sodium borohydride followed by alkylation, to prepare mixed dialkylated derivatives of Meldrum's acid is described.

Mono- vs. dialkylation of carbanions. Effects of absolute and relative acidity of the conjugate carbon acids in selectivity control

The title problem was investigated in the reaction of the dibromide 1 with carbanions 2a-2g covering a range greater than 15 pK units in DMSO. It was found that the bis(monoalkylated) product 3 arises exclusively or predominantly from the carbanions 2d-2g derived from the less acidic carbon acids 7d-7g whereas the cyclic product of dialkylation 4 prevails in the reaction of the carbanions 2a-2c derived from the more acidic carbon acids 7a-7c. The alkylation selectivity thus depends critically on the absolute acidity of the carbon acid participating in the reaction. Rationale for this novel, and on basis of earlier studies unexpected finding is provided in terms of eqs. (1)-(4).

Mitsunobu C-Alkylation of Meldrum's Acids

C-Dialkylation of Meldrum's acid (2a) and 5-benzyl Meldrum's acid (2b) can be achieved through Mitsunobu dehydration using allylic and arylmethyl alcohols as alkylating agents. This is the first time that the Mitsunobu reaction is successfully applied to the C-alkylation of a highly enolizable cyclic β-dicarbonyl system. With primary (allylic and arylmethyl) alcohols, the alkylations always take place at the carbon bearing the hydroxy group. For secondary allylic alcohols, a catalytic amount of Pd(0) must be added to enhance the regioselectivity of C-alkylation over O-alkylation. With (Ph3P)4Pd(0) as a catalyst, the reaction occurs specifically at the less hindered carbon, and the configuration of the resultant double bond is always trans. Attempts to monoalkylate Meldrum's acids 2a and 2b failed.