Regio- and stereoselective dehydrogenation of .alpha.,.omega.-diols catalyzed by a rhodium hydride complex

1986 ◽  
Vol 51 (14) ◽  
pp. 2822-2824 ◽  
Author(s):  
Youichi Ishii ◽  
Katsumi Suzuki ◽  
Takao Ikariya ◽  
Masahiko Saburi ◽  
Sadao Yoshikawa
Keyword(s):  
1964 ◽  
Vol 9 (5) ◽  
pp. 210-211
Author(s):  
WARD C. HALSTEAD
Keyword(s):  

2019 ◽  
Author(s):  
Enrico Bergamaschi ◽  
Frédéric Beltran ◽  
Christopher Teskey

<p></p><p></p><p>Switchable catalysis offers opportunities to control the rate or selectivity of a reaction <i>via</i> a stimulus such as pH or light. However, few examples of switchable catalytic systems that can facilitate multiple processes exist. Here we report a rare example of such dual-functional, switchable catalysis. Featuring an easily prepared, bench-stable cobalt(I) hydride complex in conjunction with pinacolborane, we can completely alter the reaction outcome between two widely employed transformations – olefin migration and hydroboration – with visible light as the sole trigger. This dichotomy arises from ligand photodissociation which leads to metamorphosis of the active catalytic site, resulting in divergent mechanistic pathways.</p><p></p><p></p>


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Frederick Mun ◽  
Alyssa R. Scott ◽  
David Cui ◽  
Erik B. Lehman ◽  
Seong Ho Jeong ◽  
...  

Abstract Background United States Medical Licensing Examination Step 1 will transition from numeric grading to pass/fail, sometime after January 2022. The aim of this study was to compare how program directors in orthopaedics and internal medicine perceive a pass/fail Step 1 will impact the residency application process. Methods A 27-item survey was distributed through REDCap to 161 U.S. orthopaedic residency program directors and 548 U.S. internal medicine residency program directors. Program director emails were obtained from the American Medical Association’s Fellowship and Residency Electronic Interactive Database. Results We received 58 (36.0%) orthopaedic and 125 (22.8%) internal medicine program director responses. The majority of both groups disagree with the change to pass/fail, and felt that the decision was not transparent. Both groups believe that the Step 2 Clinical Knowledge exam and clerkship grades will take on more importance. Compared to internal medicine PDs, orthopaedic PDs were significantly more likely to emphasize research, letters of recommendation from known faculty, Alpha Omega Alpha membership, leadership/extracurricular activities, audition elective rotations, and personal knowledge of the applicant. Both groups believe that allopathic students from less prestigious medical schools, osteopathic students, and international medical graduates will be disadvantaged. Orthopaedic and internal medicine program directors agree that medical schools should adopt a graded pre-clinical curriculum, and that there should be a cap on the number of residency applications a student can submit. Conclusion Orthopaedic and internal medicine program directors disagree with the change of Step 1 to pass/fail. They also believe that this transition will make the match process more difficult, and disadvantage students from less highly-regarded medical schools. Both groups will rely more heavily on the Step 2 clinical knowledge exam score, but orthopaedics will place more importance on research, letters of recommendation, Alpha Omega Alpha membership, leadership/extracurricular activities, personal knowledge of the applicant, and audition electives.


Author(s):  
Xin Cui ◽  
wei huang ◽  
Lipeng Wu

Herein, by applying zirconium-hydride complex as the catalyst, the transfer hydrogenation of quinoline and indole derivatives with ammonia borane as the proton and hydride source is achieved. Up to 94%...


1992 ◽  
Vol 47 (13-14) ◽  
pp. 3231-3246 ◽  
Author(s):  
B.L. Tarmy ◽  
C.A. Coulaloglou
Keyword(s):  

1971 ◽  
Vol 2 (11) ◽  
pp. no-no
Author(s):  
YU. P. EGOROV ◽  
V. A. KHRANOVSKII ◽  
V. V. ROSSIKHIN ◽  
N. F. KOVALENKO ◽  
L. M. YAGUPOL'SKII
Keyword(s):  

2016 ◽  
Vol 6 (12) ◽  
pp. 4428-4437 ◽  
Author(s):  
B. Butschke ◽  
M. Feller ◽  
Y. Diskin-Posner ◽  
D. Milstein

A dearomatized Fe(ii)–hydride complex mediates the hydrogenation of enolizable ketones under very mild conditions. Deactivation occursviaintramolecular proton migration.


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