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  2. Dicarbonyl - Wikipedia

    en.wikipedia.org/wiki/Dicarbonyl

    General structure of 1,2-, 1,3-, and 1,4-dicarbonyls. In organic chemistry, a dicarbonyl is a molecule containing two carbonyl (C=O) groups.Although this term could refer to any organic compound containing two carbonyl groups, it is used more specifically to describe molecules in which both carbonyls are in close enough proximity that their reactivity is changed, such as 1,2-, 1,3-, and 1,4 ...

  3. Paal–Knorr synthesis - Wikipedia

    en.wikipedia.org/wiki/Paal–Knorr_synthesis

    Also reported by Knorr is a synthesis of pyrazoles from 1,3-dicarbonyls and hydrazines, hydrazides, or semibicarbazides. This synthesis occurs via a condensation mechanism similar to the Paal-Knorr, however if a substituted hydrazine is used, it results in a mixture of regioisomers where the substituted heteroatom is either next to the R1 ...

  4. Stetter reaction - Wikipedia

    en.wikipedia.org/wiki/Stetter_reaction

    Unlike 1,3-dicarbonyls, which are easily accessed through the Claisen condensation, or 1,5-dicarbonyls, which are commonly made using a Michael reaction, 1,4-dicarbonyls are challenging substrates to synthesize, yet are valuable starting materials for several organic transformations, including the Paal–Knorr synthesis of furans and pyrroles ...

  5. Carbonyl group - Wikipedia

    en.wikipedia.org/wiki/Carbonyl_group

    Interactions between carbonyl groups and other substituents were found in a study of collagen. [3] Substituents can affect carbonyl groups by addition or subtraction of electron density by means of a sigma bond. [4] ΔHσ values are much greater when the substituents on the carbonyl group are more electronegative than carbon. [4] A carbonyl ...

  6. Organobismuth chemistry - Wikipedia

    en.wikipedia.org/wiki/Organobismuth_chemistry

    Me 3 Bi + SO 2 Cl 2 → Me 3 BiCl 2 + SO 2 Me 3 BiCl 2 + 2 MeLi → Me 5 Bi + 2 LiCl. Unstable, purple Ph 5 Bi was the first to be synthesized so. [6] Bi(V) easily forms an onium ion for example by protonation with p-toluenesulfonic acid: [19] Ph 5 Bi + HO 3 SAr → Ph 4 Bi + [O 3 SAr −] Pentaphenylbismuth forms an ate complex upon treatment ...

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    Get AOL Mail for FREE! Manage your email like never before with travel, photo & document views. Personalize your inbox with themes & tabs. You've Got Mail!

  8. Today’s NYT ‘Strands’ Hints, Spangram and Answers for ...

    www.aol.com/today-nyt-strands-hints-spangram...

    For every 3 non-theme words you find, you earn a hint. Hints show the letters of a theme word. If there is already an active hint on the board, a hint will show that word’s letter order.

  9. Scientists Link Popular Drink With Over 330,000 Deaths a Year

    www.aol.com/scientists-popular-drink-over-330...

    On a global level, researchers found that 2.2 million new cases of type 2 diabetes and 1.2 million new cases of heart disease in 2020 were attributable to SSBs — representing about 1 in 10 new ...