MétaCan
Menu
Back to cohort
Record W3199206687 · doi:10.26434/chemrxiv.11899755.v1

Direct Reversible Decarboxylation from Stable Organic Acids in Solution

2020· preprint· en· W3199206687 on OpenAlexafffund
Duanyang Kong, Patrick J. Moon, Erica K. J. Lui, Odey Bsharat, Rylan J. Lundgren

Bibliographic record

VenueChemRxiv · 2020
Typepreprint
Languageen
FieldPharmacology, Toxicology and Pharmaceutics
TopicChemical Reactions and Isotopes
Canadian institutionsUniversity of Alberta
FundersNatural Sciences and Engineering Research Council of CanadaKillam TrustsUniversity of Alberta
KeywordsDecarboxylationCarboxylationChemistryElectrophileNucleophileReactive intermediateCarbanionCarboxylateYield (engineering)Organic chemistryCombinatorial chemistryPhotochemistryCatalysis

Abstract

fetched live from OpenAlex

Many classical and emerging methodologies in organic chemistry rely on carbon dioxide extrusion to generate reactive intermediates for subsequent bond-­forming events. Synthetic reactions that involve the microscopic reverse, the carboxylation of reactive intermediates such as organometallic nucleophiles, occur under vastly different reaction conditions. We found that under appropriate conditions chemically stable C(sp3) carboxylates undergo rapid, uncatalyzed reversible decarboxylation in solution. The decarboxylation/carboxylation process occurs through the generation and trapping of otherwise undetectable carbanion intermediates that are largely resistant to protodecarboxylation in the presence of Brønsted acids or to trapping by external electrophiles. Isotopically labelled carboxylic acids, including drug molecules and valuable synthetic intermediates, can be prepared in high chemical and isotopic yield by simply supplying an atmosphere of 13CO2 to carboxylate salts in polar aprotic solvents. Our results indicate that the reversibility of decarboxylation from organic acids should be taken into consideration when designing and executing decarboxylative functionalization processes.

Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.

How this classification was reachedexpand

Full frame machine prediction

Teacher imitation

Not calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.

metaresearch head score (Codex)0.000
metaresearch head score (Gemma)0.000
Version: metacan-v3-hybrid-931329e0061cValidation status: machine_predicted_unvalidated
Candidate categoriesnone
Consensus categoriesnone
DomainCandidate signal: none · Consensus signal: none
Study designCandidate signal: Bench or experimental · Consensus signal: Bench or experimental
GenreCandidate signal: Empirical · Consensus signal: Empirical
Teacher disagreement score0.002
Threshold uncertainty score0.006

Distilled classifier scores by category (both heads)

CategoryCodexGemma
Metaresearch0.0000.000
Meta-epidemiology (narrow)0.0000.000
Meta-epidemiology (broad)0.0000.000
Bibliometrics0.0000.000
Science and technology studies0.0000.000
Scholarly communication0.0000.001
Open science0.0000.000
Research integrity0.0000.001
Insufficient payload (model declined to judge)0.0020.001

Machine scores (provisional)

The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.

Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.

Opus teacher head0.119
GPT teacher head0.390
Teacher spread0.271 · how far apart the two teachers sit on this one work
Validation statusscore_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it

Classification

machine, unvalidated

Machine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.

The models applied no category: nothing in the taxonomy fit this work.
Study designBench or experimental
Domainnot available
GenreEmpirical

How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".

Quick stats

Citations2
Published2020
Admission routes2
Has abstractyes

Explore more

Same venueChemRxivSame topicChemical Reactions and IsotopesFrench-language works237,207