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Untitled

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Sorry! I was confused by the contradicting information about boiling point and melting point on this page (which was transfered to the german wikipedia). Due to Sigma-Aldrich catalog [1], D-glyceraldehyde (97 %) is a viscous liquid, but referring to my chemistry dictionary Roempp DL-glyceraldehyde is indeed a solid of mp 145 °C, whereas the enantiomers are obtained as syrups. Thus the boiling point must be wrong :). --87.122.34.149 11:12, 10 August 2006 (UTC) [2][reply]

You are right. The reported boiling point was at reduced pressure. I've made the correction. --Ed (Edgar181) 12:46, 10 August 2006 (UTC)[reply]

Additional CAS numbers: 56-82-6 (DL-glyceraldehyde), 453-17-8 (D-glyceraldehyde) --87.122.34.149 11:43, 10 August 2006 (UTC)[reply]

Synthesis

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This article needs a citation for the synthesis claims made.Bfesser 04:00, 7 October 2007 (UTC)[reply]

tautomer or isomer of dihydroxyacetone

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I changed "tautomer" to "isomer" describing the relation of glyceraldehyde to dihydroxyacetone, and added a remark about the enzyme-catalyzed interconversion of their phosphates in glycolysis. Glyceraldehyde is an isomer of dihydroxyacetone but not a tautomer (tautomers being isomers that spontaneously interconvert under specified conditions, such as in aqueous solution at room temperature). If the two compounds were tautomers, glyceraldehyde would spontaneously lose its optical activity, because the reaction sequence

D-glyceraldehyde <=> dihydroxyacetone (achiral) <=> L-glyceraldehyde 

would soon lead to a racemic mixture of the D and L forms.CharlesHBennett (talk) 21:33, 1 December 2010 (UTC)[reply]

Picture

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It would be nice to have a photo of glyceraldehyde -- not just a diagram. I searched for images of the actual crystals and amazingly, didn't find any. Does anybody have one? — Preceding unsigned comment added by Caliroptic (talkcontribs) 21:01, 28 March 2011 (UTC)[reply]

wiki vs chemspider 3D of L-glyceraldehyde

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The wiki 3D model of L-glyceraldehyde vs the chemspider version. Why is the position of the oxygen and hydrogen of the aldehyde group switched in the two versions?

Conformational isomerism. The "geometric facts of glyceraldehyde", as with many/most covalent molecules, are only each atom's own geometry (directions of the bonds off an atom compared to others on that atom), for example, trigonal–planar vs tetrahedral, and the individualbond lengths. But each atom of a single bond freely rotates compared to each other—the molecule as a whole does not have a permanent overlall shape until you get far below room temperature. DMacks (talk) 15:39, 5 January 2016 (UTC)[reply]

Of course! You are referring to the rotation of the aldehyde group about the single bond between the aldehyde group and the alpha carbon, right? Thanks for clarifying.

Fischer projections

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The diagrams labeled as Fischer projections are not Fischer projections. Fischer projections don't show the central carbon as a C. — Preceding unsigned comment added by 2601:648:8200:79A1:886F:6A30:1DFB:DCD8 (talk) 21:45, 29 March 2019 (UTC)[reply]

Carbohydrates

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Classification of carbohydrates 103.112.27.4 (talk) 18:34, 28 November 2022 (UTC)[reply]