Rhodium-Catalyzed Annulation of Primary Benzylamine with α-Diazo Ketone toward Isoquinoline

2016 ◽  
Vol 81 (17) ◽  
pp. 8009-8013 ◽  
Author(s):  
Haoke Chu ◽  
Peiran Xue ◽  
Jin-Tao Yu ◽  
Jiang Cheng
Keyword(s):  
Diazo Ketone

Carbon–Carbon Bond Construction

2015 ◽  
Author(s):  
Douglass F. Taber
Keyword(s):  
Organic Synthesis ◽  
Grignard Reagent ◽  
Secondary Amide ◽  
State University ◽  
Wayne State University ◽  
Carbon Carbon Bond ◽  
Diazo Ketone ◽  
Peking University ◽  
Subsequent Exposure ◽  
The University

Carlo Siciliano and Angelo Liguori of the Università della Calabria showed (J. Org. Chem. 2012, 77, 10575) that an amino acid 1 could be both protected and activated with Fmoc-Cl, so subsequent exposure to diazomethane delivered the Fmoc-protected diazo ketone 2. Pei-Qiang Huang of Xiamen University activated (Angew. Chem. Int. Ed. 2012, 51, 8314) a secondary amide 3 with triflic anhydride, then added an alkyl Grignard reagent with CeCl3 to give an intermediate that was reduced to the amine 4. John C. Walton of the University of St. Andrews found (J. Am. Chem. Soc. 2012, 134, 13580) that under irradiation, titania could effect the decarboxylation of an acid 5 to give the dimer 6. Jin Kun Cha of Wayne State University demonstrated (Angew. Chem. Int. Ed. 2012, 51, 9517) that a zinc homoenolate derived from 7 could be transmetalated, then coupled with an electrophile to give the alkylated product 8. The Ramberg-Bäcklund reaction is an underdeveloped method for the construction of alkenes. Adrian L. Schwan of the University of Guelph showed (J. Org. Chem. 2012, 77, 10978) that 10 is a particularly effective brominating agent for this transformation. Daniel J. Weix of the University of Rochester coupled (J. Org. Chem. 2012, 77, 9989) the bromide 12 with the allylic carbonate 13 to give 14. The Julia-Kocienski coupling, illustrated by the addition of the anion of 16 to the aldehyde 15, has become a workhorse of organic synthesis. In general, this reaction is E selective. Jirí Pospísil of the University Catholique de Louvain demonstrated (J. Org. Chem. 2012, 77, 6358) that inclusion of a K+-sequestering agent switched the selectivity to Z. Yoichiro Kuninobu, now at the University of Tokyo, and Kazuhiko Takai of Okayama University constructed (Org. Lett. 2012, 14, 6116) the tetrasubstituted alkene 20 with high geometric control by the Re-catalyzed addition of 19 to the alkyne 18. André B. Charette of the Université de Montréal converted (Org. Lett. 2012, 14, 5464) the allylic halide 21 to the alkyne 22 by displacement with iodoform followed by elimination. In an elegant extension of his studies with alkyl tosylhydrazones, Jianbo Wang of Peking University added (J. Am. Chem. Soc. 2012, 134, 5742) an alkyne 24 to 23 to give 25.

Studies Directed Towards the Preparation of Probes for the Photoaffinity Labelling of Gibberellin Receptors

2011 ◽  
Vol 64 (4) ◽  
pp. 471 ◽  
Author(s):  
James R. Crow ◽  
Peter M. Chandler ◽  
Lewis N. Mander
Keyword(s):  
Insertion Reaction ◽  
Lower Face ◽  
Barley Endosperm ◽  
Model Studies ◽  
Receptor Sites ◽  
Diazo Ketone ◽  
Wide Range ◽  
Photoaffinity Probes ◽  
Rhodium Acetate ◽  
Gibberellin Derivatives

Model studies for the preparation of photoaffinity probes designed to explore the nature of gibberellin receptor sites have provided a wide range of gibberellin derivatives that should afford useful scaffolds incorporating auxiliary groups attached to C-2 and C-12. Methodology features the stereocontrolled opening of 2β,3β-epoxy gibberellins by attack on the lower face at C-2, while functionalization of C-12 was effected by the rhodium acetate-catalyzed CH insertion reaction of a 17-diazo ketone. Compounds were screened for bioactivity in growth and barley endosperm-based bioassays.

THEORETICAL STUDIES ON THE FORMATION MECHANISM AND STRUCTURE OF PENTAFULVENONE AND AZAFULVENONE

2008 ◽  
Vol 07 (02) ◽  
pp. 233-246 ◽  
Author(s):  
XIU-MEI PAN ◽  
XIU-JUAN JIA ◽  
YING LIU ◽  
HAO SUN ◽  
ZHONG-MIN SU ◽  
...  
Keyword(s):  
Nitrogen Atom ◽  
Potential Energy Surfaces ◽  
Vibrational Mode ◽  
Formation Mechanisms ◽  
Ortho Position ◽  
Elimination Reaction ◽  
Diazo Ketone ◽  
The Difference ◽  
Energy Surfaces ◽  
Mode Assignment

The formation mechanisms of pentafulvenone and azafulvenone were extensively investigated at the B3LYP/6-311++G** level and the potential energy surfaces were drawn out. Ketene pentafulvenone (A) and 3-carbonyl-3H-pyrrole (C) can be formed by eliminating N 2 from the diazo ketone via α elimination reaction and ketene 2-carbonyl-2H-pyrrole (B), 4-carbonyl-4H-imidazole (D), and 2-carbonyl-2H-imidazole (E) were formed by the elimination of water or methanol from pyrrole-2-carboxylic acid (rB) and carboxylate (rD and rE) via β elimination reaction. The structures of these monomers were compared and showed some information about the bond changed characters. The structure investigation indicated that the C = C bond is activated when the nitrogen atom locates in the ortho position of the C = C = O part, and therefore ortho-monomers are more facile to react. The difference of the amount and stability of the corresponding dimers are caused by differing the position and number of nitrogen atom and the variety of the ortho-dimer is complicated. In addition, the infrared spectra of the title species were also analyzed including the vibrational frequencies, IR relative intensities, and vibrational mode assignment.

Remarkable Wavelength-Dependent Photoreactions of the Bis(diazo) Ketone Having Inequivalent Diazo Groups:  Studies in Fluid Solutions and in Low-Temperature Matrixes

2000 ◽  
Vol 65 (19) ◽  
pp. 6082-6092 ◽  
Author(s):  
Shigeru Murata ◽  
Junko Kobayashi ◽  
Chiharu Kongou ◽  
Mamoru Miyata ◽  
Takeshi Matsushita ◽  
...  
Keyword(s):  
Low Temperature ◽  
Diazo Ketone
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