Alternative syntheses of bridgehead polycyclic 1,2-diamines and 2-aminoalcohols from di- and mono-oximes of some bicyclic diketones: Highly improved synthesis of tricyclo[3.3.1.03,7]nonane-3,7-diamine (original) (raw)

Investigation into the use of 1,2-diamines in fused heterocycle synthesis

Doctoral Thesis Ucl, 2012

Conclusions and Future Studies 124 3.1 Conclusions 125 University College London 7 4 Experimental 4.1 General Experimental Details 4.2 Analytical Instruments and Characterisation 4.3 Purification of Reagents 4.4 General Experimental Procedures 4.4.1 Preparation of Nitroalkenes 4.4.2 Preparation of Nitroalkanes 4.4.3 Preparation of Imines 4.4.4 Preparation of β-Nitroamines 4.4.5 Preparation of β-Nitroacetamides 4.4.6 Preparation of β-Aminoacetamides 4.4.7 Preparation of β-Aminohydroxylamines 4.4.8 Preparation of 3-Aminotetrahydroquinolines 4.4.9 Preparation of 1,2-Diamines 4.4.10 Preparation of Indolines 4.4.11 Preparation of Miscellaneous Compounds 4.4.12 Preparation of 3-Nitrotetrahydroquinolines 5 Appendices 5.1 Abbreviations 5.2 X-Ray Crystallography Data 5.3 References

Utilization of N-acyl compounds for the synthesis of tricyclic and bridged heterocyclic compounds

Global journal of chemistry

N-acyl derivative 4 was prepared via the reaction of methyl anthranilate with ethyl bromoacetate then refluxing the formed amino ester 3 with acetic anhydride. Cyclization of 4 in presences of sodium methoxide and methanol forming 2,4-pyrrolidindione derivative 5. 2,4-Quinolidinone 6 was obtained via cyclization of 4 in dry toluene and sodium hydride. On the other hand, indolinone derivative 8 was obtained by cyclization of 4 in toluene and free from alcohol due to retro Diekmann-condensation. On treatment of 8 with sodium hydride, refluxing toluene and in presences of Crown ether gave tricyclic compound 9. Also, treatment of 2-pyrrolidinone with trimethylene chlorobromide produced 10 which cyclized using base and solvent to the bridged ring derivatives 11. The acidic hydrolysis of 11 afforded the corresponding amino acid 13. Whereas derivative 14 was obtained by the reaction of 2-pyrrolidinone with ethyl 3-bromopropionate which on cyclization gave azabicyclo[3,2,1]octan-4,8-dione d...

A New, Efficient and Stereoselective Synthesis of Tricyclic and Tetracyclic Compounds by Samarium Diiodide Induced Cyclisations of Naphthyl-Substituted Arylketones—An Easy Access to Steroid-Like Skeletons

Chemistry - A European Journal, 2007

+ ] Responsible for X-ray crystal structure analysis. um diiodide was employed for new intramolecular couplings of ketyls with alkenyl, alkynyl, aryl and hetaryl substituents, yielding synthetically useful products, such as benzannulated cyclooctane and cyclooctene derivatives, [7] hexahydronaphthalenes [8] and indoles. [9] These reactions are promoted by the samarium diiodide-hexamethylphosphoramide (HMPA) complex, [10] whereupon an electron is transferred from this complex to the carbonyl group, thus generating a radical anion (samarium ketyl). Intramolecular attack of this samarium ketyl to the unsaturated functionality, followed by a second electron transfer, generates an organosamarium species, which, upon regioselective protonation, leads to the final cyclised products. The use of an excess of HMPA as an additive is in most of these cases a requirement to favour the forward reaction and to control the outcome in terms of product distribution and stereoselectivity. The samarium diiodide intramolecular couplings of g-aryl ketones A established a novel stereoselective route to hexahydronaphthalene derivatives B. [8, With this method, [13] we delivered a new solution to the challenging goal of dearomatising benzene derivatives, providing synthetically valuable functionalised intermediates of type B (Scheme 1).

Application of gamma-oxocarboxylic acids and amino acid derivatives for the preparation of heterocycles; retro Diels-Alder reactions

2005

Publications and lectures related to the thesis 1. Introduction and aims 2. Results and Discussion 2.1. Synthesis of oxomethanobenzocyclooctenecarboxylic acids and their cyclocondensation to polyheterocycles Synthesis of methanobenzocyclooctene oxo acids Cyclocondensations of methanobenzocyclooctene oxo acids to polyheterocycles 2.2. Isomerization and application of aroylnorbornenecarboxylic acids for the stereoselective preparation of heterocycles 2.3. Preparation and structure of dz'exo-norbornane-fused 1,3-heterocycles and oxanorbornane analogues Preparation and structure of ¿/z'exo-condensed norbornane heterocycles Preparation of difunctional 7-oxabicyclo[2.2.1]heptane/ene derivatives and their use for the synthesis of heterocycles 2.4. Synthesis and stereochemistry of saturated or partially saturated pyridazino[6,1-b]-and phthalazino[ 1,2-6]quinazolinones 22 2.5. Retrodiene reactions. Preparation of heterocycles by retro Diels-Alder reaction Preparation of 1-aminocyclopenta[2,3]pyrrolo[ 1,2-a]pyrimidine-2,6-dione by cycloreversion Preparation of pyrimido[2,l-a]phthalazines and an aminopyrimido[2,1-ajisoindole by retro Diels-Alder reaction 29 Double retro Diels-Alder reaction applied for the preparation of a pyrimido[ 1,2-6]pyridazine 3 3 2.6. Application of fiiran as escaping diene for the preparation of heterocycles Preparation of condensed 1,3-oxazines by retro Diels-Alder reaction 3 5 3. Summary 39 References 41 Acknowledgements Appendix Publications and lectures related to the thesis Full papers