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1.
Org Biomol Chem ; 17(22): 5520-5525, 2019 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-31120094

RESUMEN

The borylative cyclisation of 1,2-dialkynyl benzenes with BCl3 leads to dibenzopentalenes (via intramolecular SEAr) or benzofulvenes (via chloride addition) depending on substituents, with stabilised vinyl cation intermediates (e.g. with a p-MeO-C6H4-group) favouring the latter. The use of borocations leads to more selective dibenzopentalene formation, while other diyne frameworks undergo intramolecular SEAr selectively even with p-MeO groups.

2.
Angew Chem Int Ed Engl ; 56(1): 354-358, 2017 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-27897368

RESUMEN

BCl3 -induced borylative cyclization of aryl-alkynes possessing ortho-EMe (E=S, O) groups represents a simple, metal-free method for the formation of C3-borylated benzothiophenes and benzofurans. The dichloro(heteroaryl)borane primary products can be protected to form synthetically ubiquitous pinacol boronate esters or used in situ in Suzuki-Miyaura cross couplings to generate 2,3-disubstituted heteroarenes from simple alkyne precursors in one pot. In a number of cases alkyne trans-haloboration occurs alongside, or instead of, borylative cyclization and the factors controlling the reaction outcome are determined.

3.
Angew Chem Int Ed Engl ; 54(38): 11245-9, 2015 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-26237115

RESUMEN

BCl3 is an inexpensive electrophile which induces the borylative cyclization of a wide range of substituted alkynes to regioselectively form polycycles containing synthetically versatile C(sp(2) )boronate esters. It proceeds rapidly, with good yields and is compatible with a range of functional groups and substitution patterns. Intermolecular 1,2-carboboration of alkynes is also achieved using BCl3 to generate trisubstituted vinyl boronate esters.

4.
Chemistry ; 20(41): 13203-9, 2014 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-25164979

RESUMEN

N-Ylide complexes of Ir have been generated by C(sp(3))-H activation of α-pyridinium or α-imidazolium esters in reactions with [Cp*IrCl2]2 and NaOAc. These reactions are rare examples of C(sp(3))-H activation without a covalent directing group, which-even more unusually-occur α to a carbonyl group. For the reaction of the α-imidazolium ester [3H]Cl, the site selectivity of C-H activation could be controlled by the choice of metal and ligand: with [Cp*IrCl2]2 and NaOAc, C(sp(3))-H activation gave the N-ylide complex 4; in contrast, with Ag2O followed by [Cp*IrCl2]2, C(sp(2))-H activation gave the N-heterocyclic carbene complex 5. DFT calculations revealed that the N-ylide complex 4 was the kinetic product of an ambiphilic C-H activation. Examination of the computed transition state for the reaction to give 4 indicated that unlike in related reactions, the acetate ligand appears to play the dominant role in C-H bond cleavage.

5.
Clin Lung Cancer ; 15(5): 346-55, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24894943

RESUMEN

INTRODUCTION/BACKGROUND: An individual patient data metaanalysis was performed to determine clinical outcomes, and to propose a risk stratification system, related to the comprehensive treatment of patients with oligometastatic NSCLC. MATERIALS AND METHODS: After a systematic review of the literature, data were obtained on 757 NSCLC patients with 1 to 5 synchronous or metachronous metastases treated with surgical metastectomy, stereotactic radiotherapy/radiosurgery, or radical external-beam radiotherapy, and curative treatment of the primary lung cancer, from hospitals worldwide. Factors predictive of overall survival (OS) and progression-free survival were evaluated using Cox regression. Risk groups were defined using recursive partitioning analysis (RPA). Analyses were conducted on training and validating sets (two-thirds and one-third of patients, respectively). RESULTS: Median OS was 26 months, 1-year OS 70.2%, and 5-year OS 29.4%. Surgery was the most commonly used treatment for the primary tumor (635 patients [83.9%]) and metastases (339 patients [62.3%]). Factors predictive of OS were: synchronous versus metachronous metastases (P < .001), N-stage (P = .002), and adenocarcinoma histology (P = .036); the model remained predictive in the validation set (c-statistic = 0.682). In RPA, 3 risk groups were identified: low-risk, metachronous metastases (5-year OS, 47.8%); intermediate risk, synchronous metastases and N0 disease (5-year OS, 36.2%); and high risk, synchronous metastases and N1/N2 disease (5-year OS, 13.8%). CONCLUSION: Significant OS differences were observed in oligometastatic patients stratified according to type of metastatic presentation, and N status. Long-term survival is common in selected patients with metachronous oligometastases. We propose this risk classification scheme be used in guiding selection of patients for clinical trials of ablative treatment.


Asunto(s)
Adenocarcinoma/terapia , Carcinoma de Pulmón de Células no Pequeñas/terapia , Neoplasias Pulmonares/terapia , Adenocarcinoma/patología , Carcinoma de Pulmón de Células no Pequeñas/patología , Supervivencia sin Enfermedad , Humanos , Neoplasias Pulmonares/patología , Metástasis de la Neoplasia , Pronóstico , Modelos de Riesgos Proporcionales , Riesgo , Tasa de Supervivencia
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