2424-92-2Relevant articles and documents
Preparation method of long-chain aliphatic dicarboxylic acid mono-tert-butyl ester
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, (2021/07/09)
The invention provides a method for obtaining the long-chain aliphatic dicarboxylic acid mono-tert-butyl ester through monohydrolysis of the long-chain aliphatic dicarboxylic acid di-tert-butyl ester by controlling the reaction conditions of monohydrolysis; and the raw material cost is low, the yield is high, the post-treatment method is simple, and the method is suitable for industrial production.
Method for producing long-chain diacid monoester
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Paragraph 0065; 0066; 0067; 0078, (2018/08/03)
The invention provides a method for producing long-chain diacid monoester. The method comprises the following steps: carrying out reaction on diacid and benzyl alcohol or tert-butyl alcohol in tolueneunder the condition that an acidic catalyst exists; cooling a reaction solution until the residual diacid is precipitated; filtering diacid sediment; furthermore, cooling the reaction solution untilmonoester is precipitated; filtering sediment of the monoester shown as a formula I. The method provided by the invention can be used for harvesting monoester with high yield and undesired byproductsare reduced to be zero.
METHOD FOR THE SYNTHESIS OF DIACIDS OR DIESTERS FROM NATURAL FATTY ACIDS AND/OR ESTERS
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Page/Page column 6, (2010/12/29)
The invention relates to a process for the synthesis of diacids or diesters of general formula ROOC—(CH2)x—COOR, in which n is an integer between 5 and 14, R is either H or an alkyl radical of 1 to 4 carbon atoms, from natural long-chain monounsaturated fatty acids or esters including at least 10 adjacent carbon atoms per molecule of the general formula CH3—(CH2)n—CHR1—CH2—CH═CH—(CH2)p—COOR, in which R is H or an alkyl radical with 1 to 4 carbon atoms, R1 is either H or OH, and n and p, which are equal or different and are indices between 2 and 11. The method comprises: during a first step, converting the natural fatty acid or ester by pyrolysis or by ethenolysis, into a ω-monounsaturated fatty acid or ester of the general formula CH2═CH—(CH2)m—COOR, in which m is equal to p or p+1, depending on the nature of the processed fatty acid/ester and the conversion used; during a second step, submitting the product thus obtained to a metathesis or homometathesis reaction for obtaining a compound of the general formula ROOC—(CH2)m—CH═CH—(CH2)m—COOR, or cross-metathesis with a compound of formula R2OOC—(CH2)r—CH═CH—R3, in which R2 is either H or an alkyl radical front with 1 to 4 carbon atoms, r is either 0 or 1 or 2 and R3 is H, CH3 or COOR2, thus defining a cyclic or molecule or not, in order to obtain an unsaturated compound of the general formula ROOC—(CH2)m—CH═CH—(CH2)r—COOR2, and during a third step, converting the unsaturated compound into a saturated compound by hydrogenation of the double bond.
INTRAMOLECULAR END-TO-END REACTIONS OF PHOTOACTIVE TERMINAL GROUPS LINKED BY POLYMETHYLENE CHAINS.
Ashikaga,Ito,Yamamoto,Nishijima
, p. 198 - 204 (2007/10/02)
Intramolecular end-to-end reactions of a pair of photoactive terminal groups, dibenz left bracket b,f right bracket azepine (DBA) chromophores, linked by a series of polymethylene chains (DBA-CO(CH//2)//nCO-DBA, n equals 2-30) were studied by two different approaches. One approach is to measure the intramolecular deactivation rate constants of the excited triplet state of terminal DBA groups by the nanosecond laser photolysis and the other is to measure the intramolecular photocyclization rates of these bichromophoric compounds by the quantitative product analysis with GPC. The excited triplet state of the DBA group is the intermediate of the reaction.
Reduction of Isopropylidene Acylmalonates, 5-Acylbarbituric Acids, and 3-Acyl-4-hydroxycoumarins to the Corresponding Alkyl Derivatives by Sodium Cyanoborohydride-Acetic Acid
Nutaitis, Charles F.,Schultz, Rose Ann,Obaza, Judy,Smith, Francis X.
, p. 4606 - 4608 (2007/10/02)
Isopropylidene acylmalonates, 5-acylbarbituric acids, and 3-acyl-4-hydroxycoumarins are readily reduced to the corresponding alkyl derivatives by sodium cyanoborohydride-acetic acid.The cyclic substrates are readily prepared by the acylation of isopropylidene malonate, barbituric acid (or its N,N'-dimethyl derivative), and 4-hydroxycoumarin, according to procedures developed by other workers.The reductions take place upon addition of a 2 mol equiv of sodium cyanoborohydride to a mixture of the acyl compound and acetic acid.This reductive transformation completes a synthetic method for the preparation of the alkyl derivatives starting from the parent compound.
