The Cyclopropylalkylidenecyclopropane Thermal Double Ring Expansion. A Novel Route to the Bicyclo[5.3.1]undecane Skeleton of the AB Ring System of Taxanes1

1998 ◽  
Vol 120 (3) ◽  
pp. 605-606 ◽  
Author(s):  
Hong Liu ◽  
Craig A. Shook ◽  
James A. Jamison ◽  
Mohan Thiruvazhi ◽  
Theodore Cohen
Keyword(s):  
Ring Expansion ◽  
Ring System ◽  
Double Ring ◽  
Ab Ring

A concise enantioselective synthesis of the AB ring system of the manzamine alkaloids by ring-closing enyne metathesis

2001 ◽  
Vol 42 (18) ◽  
pp. 3235-3238 ◽  
Author(s):  
J.Stephen Clark ◽  
Robert J Townsend ◽  
Alexander J Blake ◽  
Simon J Teat ◽  
Amanda Johns
Keyword(s):  
Ring System ◽  
Enantioselective Synthesis ◽  
Enyne Metathesis ◽  
Manzamine Alkaloids ◽  
Ab Ring

Double Ring-transformation of Uracils to Pyrazolones via Hydantoin Ring System

Heterocycles ◽  
1982 ◽  
Vol 19 (12) ◽  
pp. 2309 ◽  
Author(s):  
Kosaku Hirota ◽  
Yoshihiro Yamada ◽  
Jun-ichi Haruta ◽  
Shigeo Senda
Keyword(s):  
Ring System ◽  
Ring Transformation ◽  
Double Ring

Entire Period Halving of Persistent Current in a Mesoscopic Double-Ring System

2001 ◽  
Vol 18 (12) ◽  
pp. 1635-1637 ◽  
Author(s):  
Wang Hai-Jun ◽  
Yi Xue-Xi ◽  
Ba Xin-Wu
Keyword(s):  
Ring System ◽  
Persistent Current ◽  
Entire Period ◽  
Double Ring

Synthetic studies related to mycobactins. III. Approaches to the synthesis of the cobactin ring system

1972 ◽  
Vol 25 (11) ◽  
pp. 2429 ◽  
Author(s):  
DSC Black ◽  
RFC Brown ◽  
AM Wade
Keyword(s):  
Primary Amine ◽  
Ring Expansion ◽  
Hydroxamic Acids ◽  
Ring System ◽  
Ethyl Benzoate ◽  
Yield Reduction ◽  
Similar Reaction ◽  
Oxidation Reactions ◽  
Cyclic Hydroxamic Acids ◽  
Synthetic Studies

The synthesis of several seven-membered cyclic hydroxamic acids has been carried out in low yield. Reduction of diethyl 2-hydroxyiminoheptane-l,7-dioate afforded ethyl 1-hydroxy-7-oxohexahydroazepine-2-carboxylate, together with related acyclic products. The cobactin precursor 3-bromo-1-hydroxyhexahydro-azepin-2-one was obtained by the ring expansion of 2-bromocyclohexanone with benzenesulphonohydroxamic acid and also by the peracid oxidation of 6-bromo-7-ethoxy-3,4,5,6-tetrahydro-2H-azepine. The methyl and cinnamyl imidates of hexanolactam were oxidized by peracid to 1-hydroxyhexahydroazepin-2-one, in addition to the related imino- and nitroso-hexanoic esters. In a similar reaction, 1-hydroxypiperidin-2-one was obtained from 2-methoxy-3,4,5,6-tetrahydropyridine. During the course of these oxidation reactions, the intermediate oxaziridines 7-methoxy-8-oxa-1-azabicyclo[5,1,0]octane and 6-bromo-7-ethoxy-8-oxa-1-azabicyclo[5,1,0]octane were isolated and identified. The peraoid oxidation of ethyl N-cyclohexylbenzimidate yielded cyclohexylhydroxylamine and ethyl benzoate in reasonable yields. This reaction suggests a useful method for the conversion of a primary amine into the related hydroxylamine.

ChemInform Abstract: AN ALTERNATE METHOD FOR CONSTRUCTION OF THE VERNOLEPIN AB-RING SYSTEM

1975 ◽  
Vol 6 (33) ◽  
pp. no-no
Author(s):  
P. A. GRIECO ◽  
J. J. REAP ◽  
J. A. NOGUEZ
Keyword(s):  
Ring System ◽  
Ab Ring

Double Ring Expansion from an Aromatic [18]Porphyrin(1.1.1.1) to an Antiaromatic [20]Porphyrin(2.1.2.1)

2016 ◽  
Vol 55 (28) ◽  
pp. 8095-8099 ◽  
Author(s):  
Masataka Umetani ◽  
Takayuki Tanaka ◽  
Taeyeon Kim ◽  
Dongho Kim ◽  
Atsuhiro Osuka
Keyword(s):  
Ring Expansion ◽  
Double Ring
Sign in / Sign up

Export Citation Format

Share Document