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Halasa-Rappel Y, Archibald J, Miller P, Frederick Lambert R, Hong M, Ng MW, Sulyanto R. Pit-and-fissure sealants on primary molars are a cost savings. J Am Dent Assoc 2021; 152:832-841.e4. [PMID: 34579809 DOI: 10.1016/j.adaj.2021.05.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 04/10/2021] [Accepted: 05/05/2021] [Indexed: 11/28/2022]
Abstract
BACKGROUND In this study, the authors examine the cost-effectiveness of light-polymerized resin-based fluoride sealants on primary molars in high caries risk children younger than 6 years. METHODS The authors examined the cost-effectiveness of pit-and-fissure sealant (PFS) treatment on primary molars by comparing sealed and unsealed molars treated in the outpatient clinic or operating room. Using 1,884 primary molars followed over a 5-year period, the authors used a mixed-effects regression model to estimate the probability of caries development. They used restricted means to estimate years free of caries for carious molars. They used a decision tree to address uncertainty due to PFS treatment failure, predict the expected value associated with each strategy, and estimate the incremental cost-effectiveness ratio using a 3% discount rate to adjust future cost and outcomes to present value. RESULTS Over 5 years, the cost of care was $90 for unsealed molars and $75 for sealed molars. Unsealed molars remained caries free for 4.32 years compared with 4.85 years in sealed molars. The cost-effectiveness of PFS treatment was dominant, leading to a savings of $25 for each caries-free year gained and overall savings of $742 million for the United States dental health system over a 5-year period. CONCLUSIONS PFS treatment is associated with cost savings and a delay in caries development and should be considered in children with high caries risk. PRACTICAL IMPLICATIONS Policy makers should consider reimbursement of PFS treatment on primary molars in high caries risk children.
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Lambert RF, Yu A, Orrell C, Haberer JE. Perceived oral health interventions by medical providers in Gugulethu, South Africa. PLoS One 2020; 15:e0233437. [PMID: 32453785 PMCID: PMC7250410 DOI: 10.1371/journal.pone.0233437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Accepted: 05/05/2020] [Indexed: 11/06/2022] Open
Abstract
Introduction The purpose of this study was to explore factors that impact patients’ ability to access high quality, expeditious oral health care by understanding medical professionals’ knowledge of oral health, the care they provide to patients presenting with oral health complaints, and their perceptions of potential interventions to improve oral health care delivery. Methods We conducted in depth qualitative interviews, which were analyzed using an inductive content analytical approach. The study was conducted in Gugulethu, a community located outside of Cape Town, South Africa. Local public sector health services provided free-of-charge are the main source of primary health and dental care for this population. Participants included the following medical providers: doctors, clinical nurse practitioners, professional nurses, and health promoters. Results Identified themes fell within the three broad subject areas: oral health knowledge, patient care, and potential interventions. Themes within oral health knowledge included (1) personal responsibility for hygiene, (2) routine oral health care, (3) lack of knowledge among medical professionals, (4) poverty, and (5) an oral-systemic connection. Participants cited both ‘clinical care knowledge’ and/or ‘uncertainty’ about patient care for oral health complaints. Participants independently suggested interventions in three broad areas: (1) education, (2) expanded provider roles, and (3) colocation of services. Conclusions Our findings suggest that a variety of interventions, ranging from high to low resource investment, may impact access to and utilization of oral health services and thereby result in improved patient care. Future studies should develop and evaluate the suggested interventions in a range of care settings.
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Affiliation(s)
- R. Frederick Lambert
- Boston Children’s Hospital, Boston, Massachusetts, United States of America
- Harvard School of Dental Medicine, Harvard University, Boston, Massachusetts, United States of America
| | - Amy Yu
- Harvard School of Dental Medicine, Harvard University, Boston, Massachusetts, United States of America
| | - Catherine Orrell
- Desmond Tutu HIV Foundation, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa
| | - Jessica E. Haberer
- Center for Global Health, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Harvard Medical School, Harvard University, Boston, Massachusetts, United States of America
- * E-mail:
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Yu A, Lambert RF, Alvarado JA, Guzman CAF, Seymour B. Integrating Competency-Based Didactic and Experiential Global Health Learning for Dental Students: The Global Health Learning Helix Model. J Dent Educ 2020; 84:438-448. [PMID: 32314384 DOI: 10.21815/jde.019.186] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Accepted: 11/04/2019] [Indexed: 11/20/2022]
Abstract
The aim of this study was to evaluate the feasibility and preliminary outcomes of immersive integrated experiential and didactic courses in strengthening competency-based global health learning in dental education. To address global inequities in oral health and student interest in global health, the Harvard School of Dental Medicine introduced two global health courses in 2017-18. The first was a didactic course in the core predoctoral curriculum, and the second, in collaboration with the Inter-American Center for Global Health, was a five-day elective experiential learning course in rural Costa Rica. The experiential course was an extension of the didactic course. All 33 second-year dental students completed the didactic course, and three of those students completed the experiential course. A pre-post survey and a six-month follow-up survey on self-reported knowledge based on course learning objectives were administered. The experiential course students also completed journals and interviews for qualitative analysis. Thirty-two students completed the pre-post didactic course surveys, for a response rate of 94%. There was a 100% response rate on the pre-post didactic surveys by those students who participated in the experiential learning course. While the experiential learning group scored similarly to the class average before the didactic course, they had higher scores than the class averages both immediately after and at the six-month follow-up. All three students reported that the experiential learning course was "extremely effective" in building on what they learned in the didactic course. Qualitative analysis of the journals and interviews suggested enhanced learning from the combination of didactic and experiential methods. These preliminary results support the Global Health Learning Helix Model, a theoretical competency-based teaching model for ethical student global health engagement to better prepare the future generation in tackling oral health disparities both locally and worldwide.
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Lambert RF, Yu A, Simon L, Cho JG, Barrow J, Seymour B. Developing an Open Access, Competency-Based Global Oral Health Curriculum: A Global Health Starter Kit. J Dent Educ 2020; 84:176-185. [PMID: 32043587 DOI: 10.21815/jde.019.176] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/25/2019] [Indexed: 11/20/2022]
Abstract
Dental education has seen increases in global health and international educational experiences in many dental schools' curricula. In response, the Consortium of Universities for Global Health's Global Oral Health Interest Group aims to develop readily available, open access resources for competency-based global oral health teaching and learning. The aim of this study was to develop and evaluate a Global Health Starter Kit (GHSK), an interdisciplinary, competency-based, open access curriculum for dental faculty members who wish to teach global oral health in their courses. Phase I (2012-17) evaluated longitudinal outcomes from two Harvard School of Dental Medicine pilot global health courses with 32 advanced and 34 predoctoral dental students. In Phase II (2018), the Phase I outcomes informed development, implementation, and evaluation of the open access GHSK (45 enrollees) written by an interdisciplinary, international team of 13 content experts and consisting of five modules: Global Trends, Global Goals, Back to Basics: Primary Care, Social Determinants and Risks, and Ethics and Sustainability. In Phase III (summer and fall 2018), five additional pilot institutions (two U.S. dental schools, one U.S. dental hygiene program, and two dental schools in low- and middle-income countries) participated in an early adoption of the GHSK curriculum. The increase in perceived knowledge scores of students enrolled in the pilot global health courses was similar to those enrolled in the GHSK, suggesting the kit educated students as well or better in nearly all categories than prior course materials. This study found the GHSK led to improvements in learning in the short term and may also contribute to long-term career planning and decision making by providing competency-based global health education.
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Mayama H, Kuwajima Y, Da Silva JD, Khorashadi S, Lambert RF, Ishida Y, Ishikawa-Nagai S, Miura H, Satoh K. <p>Cephalometric Measurements Of Non-Syndromic Oligodontia In Early Dental Age In A Japanese Population</p>. Clin Cosmet Investig Dent 2019; 11:357-365. [PMID: 31819657 PMCID: PMC6886537 DOI: 10.2147/ccide.s213111] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Accepted: 09/22/2019] [Indexed: 11/23/2022] Open
Abstract
Purpose Patients and methods Results Conclusion
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Affiliation(s)
- Hisayo Mayama
- Division of Orthodontics, Department of Developmental Oral Health Science, School of Dentistry Iwate Medical University, Morioka, Iwate, Japan
| | - Yukinori Kuwajima
- Department of Oral Medicine, Immunity and Infection, Harvard School of Dental Medicine, Boston, MA, USA
| | - John D Da Silva
- Department of Restorative Dentistry and Biomaterials Science, Harvard School of Dental Medicine, Boston, MA, USA
| | - Shahrzad Khorashadi
- Department of Oral Medicine, Immunity and Infection, Harvard School of Dental Medicine, Boston, MA, USA
| | - R Frederick Lambert
- Department of Oral Medicine, Immunity and Infection, Harvard School of Dental Medicine, Boston, MA, USA
- Department of Health Policy and Management, Harvard T. H. Chan School of Public Health, Boston, MA, USA
| | - Yoshiki Ishida
- Department of Oral Medicine, Immunity and Infection, Harvard School of Dental Medicine, Boston, MA, USA
| | - Shigemi Ishikawa-Nagai
- Department of Oral Medicine, Immunity and Infection, Harvard School of Dental Medicine, Boston, MA, USA
- Correspondence: Shigemi Ishikawa-Nagai Harvard School of Dental Medicine, 188 Longwood Avenue, Boston, MA, USATel +1-671-432-2928Fax +1-617-432-1897 Email
| | - Hiroyuki Miura
- Division of Dental Education, Department of Oral Medicine, School of Dentistry Iwate Medical University, Morioka, Iwate, Japan
| | - Kazuro Satoh
- Division of Orthodontics, Department of Developmental Oral Health Science, School of Dentistry Iwate Medical University, Morioka, Iwate, Japan
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Saffari SS, Frederick Lambert R, Dang L, Pagni S, Dragan IF. Integrating student feedback during "Dental Curriculum Hack-A-thon". BMC Med Educ 2018; 18:89. [PMID: 29720143 PMCID: PMC5930963 DOI: 10.1186/s12909-018-1189-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Accepted: 04/12/2018] [Indexed: 06/04/2023]
Abstract
BACKGROUND The future of dental education is at crossroads. This study used the parameter of the 2016 Dental Curriculum Hack-a-Thon to assess intra- and inter-institutional agreement between student and faculty views regarding dental curriculums to determine if there is an impact in student perceptions towards dental education from before and after the event. METHODS This exploratory, cross-sectional study involved two surveys, with Survey 1 being distributed among four faculty-student pairs of the four participating dental schools answering 14 questions. Survey 2 assessed the views of 20 participating dental students through 26 questions in a pre- and post- event survey design. Descriptive statistics were used to explore differences in perceptions towards dental education across both instrument surveys. RESULTS The results revealed valuable student insights regarding intra- and inter-institutional agreement relevant for the change in dental curriculum that needs to occur. Survey 2 revealed that mandatory attendance in didactic courses, electronic based examination preferences, and the preference of preclinical courses being held in the first and second years of a four-year dental curriculum were of particular importance to student participants. CONCLUSIONS The results of this study indicate that exposure and participation in subjects pertaining to dental education can be influential on student preferences and opinions on how dental education should be delivered in a four-year curriculum.
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Affiliation(s)
| | | | - Lucy Dang
- Boston University Henry M. Goldman School of Dental Medicine, Boston, USA
| | - Sarah Pagni
- Department of Public Health and Community Service, Tufts University School of Dental Medicine, Boston, USA
| | - Irina F. Dragan
- Department of Periodontology, Tufts University School of Dental Medicine, One Kneeland Street, Boston, MA 02111 USA
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Lambert RF, Wong CA, Woodmansey KF, Rowland B, Horne SO, Seymour B. A National Survey of U.S. Dental Students' Experiences with International Service Trips. J Dent Educ 2018; 82:366-372. [PMID: 29606653 DOI: 10.21815/jde.018.036] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Accepted: 10/03/2017] [Indexed: 01/26/2023]
Abstract
Globalization, along with the increasing prevalence of non-communicable diseases, their risk factors, and poor oral health, demands global approaches to oral health care. Trained health care workers' providing volunteer services abroad is one model used for improving access to dental services for some communities. Currently, little is known about U.S. dental student involvement in international clinical service volunteerism. The aim of this exploratory study was to capture national survey data from predoctoral dental students about their interest in and experience with global health service trips. The survey sought to assess students' past experiences and current and future interest in programs providing dental and/or medical services in order to lay the foundation for further research. A 12-question web-based survey was distributed in May 2017 to 22,930 students enrolled in U.S. dental schools. A total of 1,555 students responded, for a response rate of 7%. Respondents were evenly distributed across the four academic years. Approximately 22% (n=342) of the respondents had already participated in a service trip experience, 83% reported interest in a service trip while in school, and 92% were interested after graduation. Reported motivations for international trips included the desire to care for the underserved and to obtain a more global view of health and disease. Concerns were expressed regarding costs and time constraints. This study provided preliminary, exploratory data on dental student engagement with international service trips. Both interest and participation in international service trips among responding students were high, reflecting current trends in both dentistry and medicine. Dental education may have an opportunity to guide student engagement in more sustainable and ethical volunteering in the U.S. and abroad.
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Affiliation(s)
- R Frederick Lambert
- Mr. Lambert is a DMD student, Harvard School of Dental Medicine; Ms. Wong is a DMD student, Harvard School of Dental Medicine; Dr. Woodmansey is Program Director, Center for Advanced Dental Education, Saint Louis University; Ms. Rowland is Manager of International Development and Outreach, American Dental Association Foundation; Mr. Horne is Senior Manager of Marketing Research, American Dental Association Foundation; and Dr. Seymour is Assistant Professor, Department of Oral Health Policy and Epidemiology, Harvard School of Dental Medicine
| | - Chloe A Wong
- Mr. Lambert is a DMD student, Harvard School of Dental Medicine; Ms. Wong is a DMD student, Harvard School of Dental Medicine; Dr. Woodmansey is Program Director, Center for Advanced Dental Education, Saint Louis University; Ms. Rowland is Manager of International Development and Outreach, American Dental Association Foundation; Mr. Horne is Senior Manager of Marketing Research, American Dental Association Foundation; and Dr. Seymour is Assistant Professor, Department of Oral Health Policy and Epidemiology, Harvard School of Dental Medicine
| | - Karl F Woodmansey
- Mr. Lambert is a DMD student, Harvard School of Dental Medicine; Ms. Wong is a DMD student, Harvard School of Dental Medicine; Dr. Woodmansey is Program Director, Center for Advanced Dental Education, Saint Louis University; Ms. Rowland is Manager of International Development and Outreach, American Dental Association Foundation; Mr. Horne is Senior Manager of Marketing Research, American Dental Association Foundation; and Dr. Seymour is Assistant Professor, Department of Oral Health Policy and Epidemiology, Harvard School of Dental Medicine
| | - Brianna Rowland
- Mr. Lambert is a DMD student, Harvard School of Dental Medicine; Ms. Wong is a DMD student, Harvard School of Dental Medicine; Dr. Woodmansey is Program Director, Center for Advanced Dental Education, Saint Louis University; Ms. Rowland is Manager of International Development and Outreach, American Dental Association Foundation; Mr. Horne is Senior Manager of Marketing Research, American Dental Association Foundation; and Dr. Seymour is Assistant Professor, Department of Oral Health Policy and Epidemiology, Harvard School of Dental Medicine
| | - Steven O Horne
- Mr. Lambert is a DMD student, Harvard School of Dental Medicine; Ms. Wong is a DMD student, Harvard School of Dental Medicine; Dr. Woodmansey is Program Director, Center for Advanced Dental Education, Saint Louis University; Ms. Rowland is Manager of International Development and Outreach, American Dental Association Foundation; Mr. Horne is Senior Manager of Marketing Research, American Dental Association Foundation; and Dr. Seymour is Assistant Professor, Department of Oral Health Policy and Epidemiology, Harvard School of Dental Medicine
| | - Brittany Seymour
- Mr. Lambert is a DMD student, Harvard School of Dental Medicine; Ms. Wong is a DMD student, Harvard School of Dental Medicine; Dr. Woodmansey is Program Director, Center for Advanced Dental Education, Saint Louis University; Ms. Rowland is Manager of International Development and Outreach, American Dental Association Foundation; Mr. Horne is Senior Manager of Marketing Research, American Dental Association Foundation; and Dr. Seymour is Assistant Professor, Department of Oral Health Policy and Epidemiology, Harvard School of Dental Medicine.
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Lambert RF, Orrell C, Bangsberg DR, Haberer JE. Factors that Motivated Otherwise Healthy HIV-Positive Young Adults to Access HIV Testing and Treatment in South Africa. AIDS Behav 2018; 22:733-741. [PMID: 28190116 DOI: 10.1007/s10461-017-1704-y] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The World Health Organization recommends early initiation of HIV antiretroviral therapy (ART) for all those infected with the virus at any CD4 count. Successfully reaching individuals with relatively high CD4 counts depends in large part on healthy individuals seeking testing and treatment; however, little is known about factors motivating this decision. We conducted a qualitative study to explore this issue among 25 young HIV-positive adults (age 18-35) with a CD4 count >350 cells/mm3 who recently started or made the decision to start ART in Gugulethu, South Africa. Using an inductive content analytical approach, we found that most individuals sought testing and treatment early in the disease progression because of a desire to appear healthy thereby avoiding stigma associated with AIDS. Other factors included social support, responsibilities and aspirations, normalcy of having HIV, and accessible services. These findings suggest that maintenance of physical appearance should be included in the development of novel testing and treatment interventions.
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Affiliation(s)
| | - Catherine Orrell
- Desmond Tutu HIV Foundation, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa
| | - David R Bangsberg
- Center for Global Health, Massachusetts General Hospital, 125 Nashua St, Suite 722, Boston, MA, 02114, USA
- Harvard Medical School, Harvard University, Boston, MA, USA
| | - Jessica E Haberer
- Center for Global Health, Massachusetts General Hospital, 125 Nashua St, Suite 722, Boston, MA, 02114, USA.
- Harvard Medical School, Harvard University, Boston, MA, USA.
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Lambert RF, Orrell C, Haberer JE. "It was pain. That's it. It was pain." Lack of oral health care among otherwise healthy young adults living with HIV in South Africa: A qualitative study. PLoS One 2017; 12:e0188353. [PMID: 29272290 PMCID: PMC5741215 DOI: 10.1371/journal.pone.0188353] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2017] [Accepted: 11/06/2017] [Indexed: 01/10/2023] Open
Abstract
INTRODUCTION The purpose of this study is to understand engagement with and availability of dental services among people living with HIV in a low-income community of South Africa. METHODS In depth qualitative interviewing was used to collect data, which was analyzed using an inductive content analytical approach. The study was conducted in Gugulethu, a township community located outside of Cape Town, South Africa. Local public sector health services provided free of charge are the main source of primary health and dental care for this population. Participants included South African adults (age 18-35) recently diagnosed with HIV who had a CD4 count >350 cells/mm3. RESULTS Many participants had little to no experience with dental care, did not know which health care providers are appropriate to address oral health concerns, were not aware of available dental services, utilized home remedies to treat oral health problems, harbored many misperceptions of dental care, avoided dental services due to fear, and experienced poverty as a barrier to dental services. CONCLUSIONS Our findings suggest that integration of oral healthcare into medical care may increase patient knowledge about oral health and access to care. Leveraging the relatively robust HIV infrastructure to address oral disease may also be an effective approach to reaching these participants and those living in resource poor communities generally.
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Affiliation(s)
- R. Frederick Lambert
- Harvard School of Dental Medicine, Harvard University, Boston, MA, United States of America
| | - Catherine Orrell
- Desmond Tutu HIV Foundation, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa
| | - Jessica E. Haberer
- Center for Global Health, Massachusetts General Hospital, Boston, MA, United States of America
- Harvard Medical School, Harvard University, Boston, MA, United States of America
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Graham TJA, Lambert RF, Ploessl K, Kung HF, Doyle AG. Enantioselective Radiosynthesis of Positron Emission Tomography (PET) Tracers Containing [18F]Fluorohydrins. J Am Chem Soc 2014; 136:5291-4. [DOI: 10.1021/ja5025645] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Thomas J. A. Graham
- Department
of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - R. Frederick Lambert
- Department
of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Karl Ploessl
- Department
of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Hank F. Kung
- Department
of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
- Department
of Pharmacology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Abigail G. Doyle
- Department
of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
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Lambert RF, Hinkle RJ, Ammann SE, Lian Y, Liu J, Lewis SE, Pike RD. Bi(OTf)3-, TfOH-, and TMSOTf-mediated, one-pot epoxide rearrangement, addition, and intramolecular silyl-modified Sakurai (ISMS) cascade toward dihydropyrans: comparison of catalysts and role of Bi(OTf)3. J Org Chem 2011; 76:9269-77. [PMID: 21916500 PMCID: PMC3359705 DOI: 10.1021/jo201478d] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Catalytic quantities of bismuth(III) triflate efficiently initiate the rearrangement of epoxides to aldehydes, which subsequently react with (Z)-δ-hydroxyalkenylsilanes to afford 2,6-disubstituted 3,6-dihydro-2H-pyrans. Isolated yields of desired products using Bi(OTf)(3) were compared with yields obtained when the reactions were run with TfOH and TMSOTf in the presence and absence of several additives. These studies, as well as NMR spectroscopic analyses, indicate an initial Lewis acid/base interaction between Bi(OTf)(3) and substrates providing TfOH in situ.
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Affiliation(s)
- R. Frederick Lambert
- Department of Chemistry, The College of William & Mary, P.O. Box 8795, Williamsburg, VA 23187-8795
| | - Robert J. Hinkle
- Department of Chemistry, The College of William & Mary, P.O. Box 8795, Williamsburg, VA 23187-8795
| | - Stephen E. Ammann
- Department of Chemistry, The College of William & Mary, P.O. Box 8795, Williamsburg, VA 23187-8795
| | - Yajing Lian
- Department of Chemistry, The College of William & Mary, P.O. Box 8795, Williamsburg, VA 23187-8795
| | - Jia Liu
- Department of Chemistry, The College of William & Mary, P.O. Box 8795, Williamsburg, VA 23187-8795
| | - Shane E. Lewis
- Department of Chemistry, The College of William & Mary, P.O. Box 8795, Williamsburg, VA 23187-8795
| | - Robert D. Pike
- Department of Chemistry, The College of William & Mary, P.O. Box 8795, Williamsburg, VA 23187-8795
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