Aromatic 5-silicon rings synthesized at last
cen.acs.org

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67 points

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keepamovin

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3 days ago

28 comments

snitty ・ 7 hours ago

>Move over cyclopentadiene anion—there’s a new five-membered aromatic ring in town, and this one is made of silicon.

CHEM-Es are build a little different from the rest of us.

  • nerdsniper ・ 6 hours ago

    Chemists really. Chem-E’s basically just play IRL Factorio at work. The graphs in Factorio look almost exactly like OSI PiSoft charts, which basically every chemical plant uses.

  • gilleain ・ 6 hours ago

    Cyclopentadiene is a great molecule - it can form 'metallocene' compounds where two cyclopentadiene (Cp) rings 'sandwich' a metal ion between them:

    https://en.wikipedia.org/wiki/Metallocene

    Like Cp--M--Cp where the '--' are an unusual kind of 'bond' which is somewhat like five carbon-metal bonds, although I'm sure there is a more accurate orbital description of the interaction.

    • theideaofcoffee ・ 5 hours ago

      The ‘--‘ is a ligand bond, a fundamental aspect of coordination and organometallic chemistry.

  • bonzini ・ 6 hours ago

    "The average person probably only knows the formulas for olivine and one or two feldspars" (https://xkcd.com/2501)

    • robwwilliams ・ 6 hours ago

      Perfect! I read this “heart-warming” overview of two papers in Science and learned zero about why this is of any significance. The discovery is significant but I had to probe Opus 4.6 to find out why.

      The personal focus is a distraction. It would be great if science writers could focus on the science and significance of the advance.

  • theideaofcoffee ・ 6 hours ago

    Nah, this is just a strict chemical synthesis problem, no need for the engineers yet, until you want to make ten thousand tons of the stuff.

rbanffy ・ 7 hours ago

Any possible applications?

  • ultratalk ・ 7 hours ago

    > Iwamoto and Scheschkewitz say pentasilacyclopentadienides could be ligands for catalysts and materials.

    • robwwilliams ・ 6 hours ago

      The review should have expanded on this at a practical level even mom and dad could understand—the standard “better life through chemistry” angle.

    • frederikvs ・ 5 hours ago

      Sounds like it could improve the production efficiency of glyptal-impregnated, cyanoethylated bushings for turbo-encabulators!

cubefox ・ 7 hours ago

So what was their aroma like?

  • snitty ・ 7 hours ago

    In this case aromatic means a ring of atoms where there is electron sharing among all the members of the ring.

    They're called aromatic rings because before they understood the structure, they grouped them by their behavior, and the aromatics contain a lot of volatile organics like benzene, toluene, phenol, which have strong odors.

    • moffkalast ・ 5 hours ago

      So it's not volatile enough to give off a scent?

      • jaggederest ・ 4 hours ago

        Massive molecule with a lithium salt on every silicon atom. It's not going to have basically any vapor pressure and thus effectively no aroma unless there are breakdown products

      • jfengel ・ 3 hours ago
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        Even if it were volatile, you likely wouldn't be able to smell it. The olfactory sense is complicated and weird, and targeted at organic chemistry. You can smell a few inorganic things (notably, elemental osmium, whose name literally means "smell" because that's so unusual), but your receptors are unlikely to trigger for anything that far removed.

  • analog31 ・ 5 hours ago

    If you know, you're probably dead.

  • andrewflnr ・ 5 hours ago

    "Characteristic", no doubt.

YarickR2 ・ 7 hours ago

So, we have a chance to reduce our usage of volatile hydrocarbons. Silicon-based chemicals should not burn as easily as CH-based ones.

  • gus_massa ・ 7 hours ago

    No, it's a super weird molecule that is big, expensive to make and probably form a solid. It can not replace solvents like benzene.

    The weird structure of the electrons in the silicon cycle may be useful as a catalyst(or not, it's too early to be sure). Imagine it is like the Platinum in the car exhaust, not the solvent in the paint remover.

  • adrian_b ・ 7 hours ago

    This particular silicon compound is unlikely to help much in that direction.

    On the other hand, silicone resins and elastomers are already in widespread use in applications where resistance to high temperatures or burning is required (silicone =/= silicon, the former coming from silic-on + ket-one, a name based on a wrong hypothesis).

    However, their mechanical resistance is usually modest, so if that is important they must be used either in combinations with other materials or reinforced, e.g. with glass fiber.

    They are also more expensive than hydrocarbon-based plastics, so they are typically used only where strictly necessary.