Synthesis of 2a,8b-Dihydrocyclobuta[a]naphthalene-3,4-diones.

Beilstein J Org Chem

Chemistry Department, University of Hamburg, Martin-Luther-King Platz 6, D-20146 Hamburg, Germany.

Published: July 2010

On irradiation (λ = 350 nm) in neat hex-1-yne, naphthalene-1,2-dione monoacetals 1 afford mixtures of pentacyclic photodimers and up to 25% (isolated yield) of mixed photocycloadducts 2. Careful acidic hydrolysis of the acetal function of 2 gives the title compounds 3, the overall sequence representing a first approach to a (formal) [2 + 2] photocycloadduct of a 1,2-naphthoquinone to an alkyne.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2919270PMC
http://dx.doi.org/10.3762/bjoc.6.76DOI Listing

Publication Analysis

Top Keywords

synthesis 2a8b-dihydrocyclobuta[a]naphthalene-34-diones
4
2a8b-dihydrocyclobuta[a]naphthalene-34-diones irradiation
4
irradiation 350
4
350 neat
4
neat hex-1-yne
4
hex-1-yne naphthalene-12-dione
4
naphthalene-12-dione monoacetals
4
monoacetals afford
4
afford mixtures
4
mixtures pentacyclic
4

Similar Publications

Synthesis of complex, multiring, spirocyclic, 1,3-dicarbonyl fused, and highly functionalized 5-phenyl-1-azabicyclo[3.1.0]hexanes (ABCH) has been achieved by an intermolecular reaction of 2-(2'-ketoalkyl)-1,3-indandiones or α,γ-diketo esters with (1-azidovinyl)benzenes under transition metal-free conditions.

View Article and Find Full Text PDF

A novel silver-catalyzed cascade radical isonitrile insertion and defluorinative cyclization have been developed to synthesize CFH- and phosphinoyl-containing quinolines from -isocyanyl α-trifluoromethylstyrenes. The reaction proceeded under redox-neutral conditions and allowed the construction of a highly attractive quinoline ring system, with the simultaneous formation of the CFH group and introduction of various phosphinoyl groups in a single transformation, showing operational simplicity, a wide substrate scope, good tolerance for functional groups, and remarkable atom-/stepeconomy. Mechanistic studies indicated that the reaction is likely to involve the participation of P-centered radicals and key carbanion intermediates.

View Article and Find Full Text PDF

The Importance of Frailty in Older Adults With Benign Paroxysmal Positioning Vertigo.

J Neurol Phys Ther

November 2024

Faculty of Rehabilitation Sciences, REVAL-Rehabilitation Research Centre, Hasselt University, Hasselt Diepenbeek, Limburg, Belgium (S.P., P.M., J.S.); Department of Otorhinolaryngology and Head & Neck Surgery, School for Mental Health and Neuroscience, Faculty of Health Medicine and Life Sciences, Maastricht University Medical Centre, The Netherlands (S.P., R.V.D.B); Department of Otorhinolaryngology, Head and Neck Surgery ZOL Hospital, Belgium (N.L., W.L.); and Department of Nutrition and Movement Sciences, NUTRIM Institute of Nutrition and Translational Research in Metabolism, Maastricht University, The Netherlands (K.M.).

Background And Purpose: Even though Benign Paroxysmal Positioning Vertigo (BPPV) is one of the most reported vestibular disorders, its interaction with frailty and postural control in older adults is hardly or not investigated.

Methods: Thirty-seven older adults (≥65 years) with a diagnosis of BPPV (oaBPPV) (mean age 73.13 (4.

View Article and Find Full Text PDF

Effectiveness of Synchronous Postdischarge Contacts on Health Care Use and Patient Satisfaction : A Systematic Review and Meta-analysis.

Ann Intern Med

January 2025

Center of Innovation to Accelerate Discovery and Practice Transformation, Durham Veterans Affairs Health Care System; Department of Population Health Sciences, Duke University School of Medicine; and Durham Evidence Synthesis Program, Durham Veterans Affairs Health Care System, Durham, North Carolina (J.M.G.).

Background: Postdischarge contacts (PDCs) after hospitalization are common practice, but their effectiveness in reducing use of acute care after discharge remains unclear.

Purpose: To assess the effects of PDC on 30-day emergency department (ED) visits, 30-day hospital readmissions, and patient satisfaction.

Data Sources: MEDLINE, Embase, and CINAHL searched from 2012 to 25 May 2023.

View Article and Find Full Text PDF

Background: HIV/AIDS remains a significant global challenge, and with the rapid advancement of technology, there has been an increasing number of interventions aimed at improving HIV/AIDS cognition and self-management behaviors among patients. However, there is still a lack of detailed literature integrating relevant evidence.

Objective: This study aims to comprehensively review existing research on interventions using modern information methods to improve HIV/AIDS cognition and enhance self-management behaviors among patients.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!