The Diels-Alder reaction of transient nitrosoguanidines: a new class of N-O heterodienophiles and a novel method for the synthesis of functionalized guanidines
Bibliographic record
Abstract
This thesis is a summary of research conducted since September 2001 at the University of Toronto in the laboratory of Dr. Robert A. Batey. This manuscript is divided into two chapters. In chapter one, the Diels-Alder reaction of nitrosoguanidines is discussed. This includes the intermolecular, intramolecular and diastereoselective versions of the reaction. In all cases, the reaction proceeds via oxidation of a hydroxylguanidine to generate a transient nitrosoguanidine intermediate that is subsequently trapped in situ with a 1,3-diene. The reaction proceeds in high yield and excellent regioselectivity and constitutes a new class of N-O heterodienophiles. Chapter two details the synthesis of functionalized guanidines via simple transformations of the initial cycloadducts discussed in chapter one. Simple manipulations of the cycloadducts generated via this novel methodology can generate a number of synthetically useful guanidines in high yield and few synthetic steps. Finally the synthesis of a number of “privileged” guanidine structures is discussed featuring this methodology.
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 imitationNot 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.
Distilled classifier scores by category (both heads)
| 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) | 0.002 | 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 source (direct Gemma or distilled Codex), 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".