ChemInform Abstract: RECENT DEVELOPMENTS IN CARBODIIMIDE CHEMISTRY

Mikołajczyk, M.; Kiełbasiński, P.

doi:10.1002/chin.198124356

Cited by 5 publications

(5 citation statements)

References 1 publication

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“…Carbodiimides do not react readily with alcohols in water solution without catalyst. 27 However, cellobiose can be oxidized and there is a possibility that it might reduce the carbodiimide. Such an inactivation of the reagent would probably not have given rise to the effects observed.…”

Section: Resultsmentioning

confidence: 99%

Studies on the enantioselective retention mechanisms of cellobiohydrolase I (CBH I) by covalent modification of the intact and fragmented protein

et al. 1998

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In order to elucidate the chiral recognition mechanisms of the enzyme cellobiohydrolase I (CBH I), its carboxylic groups were covalently modified. The synthetic modification was carried out either in the presence or absence of cellobiose, which has proven to inhibit the enzymatic activity and if present in the mobile phase impairs enantioselectivity of amino alcohols. Compared to the reference CSP (unmodified CBH‐I silica and CBH‐I core silica), the synthetically modified phases show differences both in enantioselectivity and retention. The enzymatic differences between the CSPs were also in line with the chromatographic results. The selectivity factors of propranolol are almost unchanged during the reaction periods in the presence of cellobiose, while they decreased rapidly without the inhibitor. In one case, even a slight improvement in enantioselectivity was obtained, indicating that non‐stereospecific carboxylic groups were ruled out. Chirality 10:760–769, 1998. © 1998 Wiley‐Liss, Inc.

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Section: Resultsmentioning

confidence: 99%

Studies on the enantioselective retention mechanisms of cellobiohydrolase I (CBH I) by covalent modification of the intact and fragmented protein

et al. 1998

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“…It is also extensively used for building peptide and amide linkages [8]. Roy and Bhaduri [9] have reported DCC as donor of cyclohexyl amine during amidation of carboxylic acids.…”

Section: Introductionmentioning

confidence: 99%

Direct esterification of fatty acids with phenylalkanols by using dicyclohexylcarbodiimide

Parveen

2004

Euro J Lipid Sci & Tech

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A mild one-pot esterification method of fatty acids with alcohols at room temperature is described. The reaction of undec-10-enoic acid (I) with 1-phenylethanol in the presence of N,N'-di-cyclohexylcarbodiimide and 4-(N,N-dimethylamino)pyridine gave 1'-phenylethyl undec-10-enoate in quantitative yield. Similar reactions were also carried out with (Z)-octadec-9-enoic acid, (Z)-12-hydroxyoctadec-9-enoic and (Z)-9-hydroxyoctadec-12-enoic acids. In addition, compound (I) was allowed to react with diphenyl methanol to form its corresponding ester. The structure elucidation of the prepared esters is based on the elemental analysis and spectral data (IR, 1 H-and 13 C-NMR, MS).

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“…30 Thus, the ease of cyclization and the nucleophilicity of the acid anion are predominant factors in dictating the nature of the final product. 30,31,51,53 The reaction of phthalic acid, for which the carboxyl groups are so placed as to facilitate intramolecular anhydride formation, has been reported to result, with a variety of carbodiimides, in anhydride formation solely. 2,30 Results presented here indeed confirm the formation of the anhydride, while no trace of N-acylurea (Fig.…”

Section: Resultsmentioning

confidence: 99%

Use of Fourier Transform Infrared Spectroscopy to Follow the Heterocumulene Aided Thermal Dehydration of Phthalic and Naphthalic Acids

Rigout

Lewis

2006

Appl Spectrosc

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Fourier transform infrared (FT-IR) spectroscopy has been successfully employed to follow the formation of phthalic anhydride and 1,8-naphthalic anhydride on heating their corresponding acids. The effects of three heterocumulenes, cyanamide, dicyandiamide, and sodium cyanate, on the temperature of formation of the anhydrides were also investigated using this method. It was found that the carbodiimides cyanamide and dicyandiamide dramatically lowered the temperature at which thermal dehydration of the acid led to anhydride formation. It was noted that cyanamide had a stronger catalytic effect than dicyandiamide, presumably due to the electron-withdrawing effect of the amidine group. Sodium cyanate was also found to promote the thermal dehydration of the acids to form the corresponding anhydrides. Under more severe conditions, phthalic acid anhydride formed is seen to react further, leading to the formation of phthalimide. The discrepancy between the products obtained with cyanamide and sodium cyanate leads to the conclusion that, unlike earlier claims, imide formation is not due to the reaction of the anhydride with the urea formed but with sodium cyanate itself. However, only the phthalic anhydride five-membered ring system is sufficiently reactive towards the CNO- nucleophile to form the imide; the six-membered 1,8-naphthalic anhydride system does not react in this way.

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ChemInform Abstract: RECENT DEVELOPMENTS IN CARBODIIMIDE CHEMISTRY

Cited by 5 publications

References 1 publication

Studies on the enantioselective retention mechanisms of cellobiohydrolase I (CBH I) by covalent modification of the intact and fragmented protein

Studies on the enantioselective retention mechanisms of cellobiohydrolase I (CBH I) by covalent modification of the intact and fragmented protein

Direct esterification of fatty acids with phenylalkanols by using dicyclohexylcarbodiimide

Use of Fourier Transform Infrared Spectroscopy to Follow the Heterocumulene Aided Thermal Dehydration of Phthalic and Naphthalic Acids

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