Kinetics and Mechanisms of the Reactions of Diaryl- and Dialkylgermylenes with Alcohols and Ethers in Solution
Bibliographic record
Abstract
The reactions of methanol, tert -butanol, and THF with a series of simple germylene derivatives dimethyl- (GeMe 2 ), diphenyl- (GePh 2 ), and dimesitylgermylene (GeMes 2; Mes = 2,4,6-trimethylphenyl) have been studied in hexane solution at 25 °C by laser flash photolysis methods. The results are consistent with rapid, reversible reaction to form weakly stabilized Lewis acid−base complexes, which exhibit UV absorption maxima in the range 290−360 nm and decay with mixed order kinetics with concomitant formation of the corresponding digermene, Ge 2 R 4 (R = Me, Ph, or Mes). Absolute rate constants for formation of the complexes could be measured for GePh 2 with all three substrates and for GeMe 2 with THF and were found to vary over the range (4−10) × 10 9 M -1 s -1 . Equilibrium constants were measured in all cases; they vary between 1.2 and 15 M -1 for GeMes 2, decreasing in the order MeOH > t-BuOH > THF, while those for GeMe 2 and GePh 2 are 2−4 orders of magnitude larger and decrease in the order THF > MeOH > t-BuOH. For a given substrate, the equilibrium constants are consistently larger for GePh 2 than for GeMe 2, reflecting the greater ability of phenyl compared to methyl substituents to stabilize negative charge at germanium in the zwitterionic complexes. In spite of the differences in the stabilities of the complexes, the rate constant for complexation with THF is almost twice as large for GeMe 2 than for GePh 2 . The results indicate that the O−H insertion reaction of germylenes with alcohols proceeds via initial, reversible Lewis acid−base complexation, followed by slow proton transfer from oxygen to germanium, most likely via a catalytic route.
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 distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
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.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
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".