Synthesis of Bicyclic and Tricyclic Chiral Guanidinium Salts by an Intramolecular Alkylation Approach

2016 ◽  
Vol 2017 (2) ◽  
pp. 296-305
Author(s):  
Aleksej Turočkin ◽  
William Raven ◽  
Philipp Selig
2020 ◽  
Vol 75 (6-7) ◽  
pp. 685-695
Author(s):  
Willi Kantlehner ◽  
Ioannis Tiritiris ◽  
Wolfgang Frey ◽  
Ralf Kreß

AbstractBis[bis(dibutylamino)methylen]hydrazine 8 is prepared from N,N,N′,N′-tetrabutylchloroformamidinium chloride (4c) and hydrazine. Bromine transforms 8 to the heterocyclic guanidinium salt 15a which is isolated as tetraphenylborate. From N,N,N′,N′-tetraalkylchloroformamidiniumchlorides and ethylendiamine the diguanidines are prepared which are alkylated to give diguanidinium salts, From these salts guanidinium salts can be prepared by anion metathesis with tetraphenylborate-, iodide-, hexafluorphosphate-, trifluoromethansulfonat-, bis(trifluormethansulfonyl)imide and tricyanmethanide as counteranions. The structure of the compounds 15 and 17b is confirmed by crystal structure analyses.


2004 ◽  
Vol 82 (5) ◽  
pp. 571-578 ◽  
Author(s):  
Kirill V Nikitin ◽  
Nonna P Andryukhova

Under basic conditions (lithium diisopropylamide or sodium hydride in THF) 2-(2-bromoethoxy)-acetophenones were transformed to 3,4-dihydro[1]benzoxepin-5(2H)-ones (homochromanones) in high yields. The preparation of novel tetrahydropyrano[2,3-b]pyrrol-6(2H)-ones and 3,4-dihydro-2H-pyrrolo[2,1-b][1,3]oxazin-6(8aH)-ones and spiro compounds was performed using similar cyclization in moderate to good yields.Key words: cyclization, lithiation, spiro heterocycles.


2004 ◽  
Vol 82 (2) ◽  
pp. 113-119 ◽  
Author(s):  
William R Barton ◽  
Leo A Paquette

Reaction of N-substituted bromomethanesulfonamides with 2 equiv of potassium carbonate and an α-halo ketone, ester, or nitrile leads directly to 3-substituted β-sultams. The first step is intermolecular and is followed by an intramolecular alkylation. The process is particularly efficient when diethyl bromomalonate and 3-chloro-2-butanone are involved. In the latter example, no competitive cyclization to form a six-membered ring is seen. The functional groups in certain of the β-sultam products can be subsequently manipulated to give bicyclic products.Key words: β-sultams, intramolecular SN2 displacement, sulfonamides, ring closing metathesis, four-membered heterocycles.


1971 ◽  
Vol 1 (1) ◽  
pp. 51-73 ◽  
Author(s):  
Ajay K. Bose ◽  
M. S. Manhas ◽  
B. G. Chatterjce ◽  
R. F. Abdulla

1979 ◽  
Vol 41 (7) ◽  
pp. 937-940 ◽  
Author(s):  
Chris J. Adams ◽  
John M. Adams ◽  
Robin G. Pritchard ◽  
Vijayalakshmi Ramdas

2017 ◽  
Vol 19 (15) ◽  
pp. 9724-9728 ◽  
Author(s):  
V. Balos ◽  
M. Bonn ◽  
J. Hunger

The interaction of spherical anions and cations with a model amide is additive, except for salts containing the guanidinium cation.


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