User talk:Stanimirstanchev

CHRISTO IVANOV - outstanding Bulgarian chemist, Professor; born in the town of Dobrich, Bulgaria on May 3, 1916. His father Ivan Christov was hardware man and cartwright. Coming back as a disabled soldier from the World War I he died 1918. His mother, Elena Christova, took care of her one and only son.



Life and career
Christo Ivanov obtained his degree in chemistry from the Physical-Mathematical Faculty of Sofia University in 1939. After teaching Chemistry at school level in the towns of Popovo and Karlovo for a couple of years, he received the position of regular Assistant Professor at the same faculty in 1946. He has specialized in the field of Organic Synthesis at the universities of Leipzig (1953-1954) and Moscow (1956-1957). His scientific career is associated with the University of Sofia – its Physical-Mathematical Faculty and the later Faculty of Chemistry that branched off from it (1961). He was habilitated as Associate Professor in 1957 and received full Professorship and the Chair of Organic Chemistry in 1963. Prof. Ivanov was the Head of the same department from 1963 to his retirement in 1984. Besides, he was Vice Rector of Sofia University (1962-1968), Dean of the Faculty of Chemistry (1972-1976), President of the Commission of Chemical Sciences at the Higher Attestation Commission and a member of the Presidium of the latter commission between 1980 and 1986.

The well-known Bulgarian organic chemist passed away on February 16, 2004 at the age of 87 after a short illness. The Bulgarian organic chemists lost with his death a prominent scientist, an outstanding pedagogue and a dear colleague.

Scientific works
Prof. Christo Ivanov continued the research started by Academician Dimitar Ivanov and his studies published in over 125 scientific papers raised the authority of the Bulgarian school of Organic Chemistry to international standards. Initially, he worked on the composition of various Bulgarian essential oils but his most significant achievements were in the field of Organic Synthesis. His main interests focused on the reactivity of CH-acidic compounds in an attempt to solve fundamental problems in the chemistry of carbanions and organometallic compounds. The results obtained enabled the elaboration of various synthetic methods for preparation of new organic compounds.

In collaboration with Prof. Peter Markov, Prof. Christo Ivanov established for the first time the possibility for metalation of CH-acidic compounds with magnesium in liquid ammonia. He attempted to elucidate the structure of the prepared organomagnesium compounds and explained the obtained results with the phenomenon of metalotropy. In acknowledgement of these scientific achievements the team were given in l979 the Prof. Assen Zlatarov Award by the Bulgarian Academy of Sciences.

The Laboratory of Organic Synthesis supervised by Prof. Ivanov has come by interesting results. New synthetic methods have been developed on the basis of a reaction of ambident nuclephilic reagents (prepared by metalation of esters, nitriles and amides of alkanoic and arylacetic acids) with N-acylated aldimines and ketimines. The resulting new derivatives of 3-acylaminopropanoic acids have been transformed into various heterocyclic compounds: beta-lactams, 1,3-oxazines, 2-imidazolidinones, etc. A new method has been proposed for the synthesis of morpholine derivatives with interesting biological activity starting from the easily available 4-alkyl-3-morpholinones.

The reaction of 2-benzylbenzazoles with aromatic aldehydes has studied in detail under phase-transfer catalysis or in aprotic solvents in the presence of a water solution of sodium hydroxide leading to 2-styrylbenzazols or alcohols having a benzazole ring. Extensive studies have been done on the reaction of deprotonated CH-acidic compounds such as N-benzyldenebenzylamine with aldehydes yielding 1,2-diaryl-2-aminoalcohols. Significant attention has been paid to the cycloaddition of these compounds or derivatives of N-(diphenylmethyleneamino)-acetic acid to alpha,beta-unsaturated ketones, esters, nitriles, azomethines, etc. Thus, various new polyfunctional organic compounds were prepared.

Detailed studies have been done under the conditions of the Michael reaction on the addition of metallic derivatives of CH-acidic compounds to substrates containing carbonyl or azomethine group or to substrates with an activated double bond.

Prof. Ivanov was the initiator of studies on the reaction of nucleophilic reagents with coumarins. A new interesting rearrangement of 3-substituted coumarins to 2-oxochromans-4-acetic acid derivatives was found for the first time. It is used for elaboration of preparative methods for conversion of nitriles, esters and amides of coumarin-3-carboxylic acid into the corresponding rearranged products.

Teaching
Prof. Chr. Ivanov was also a brilliant lecturer and pedagogue. He raised the teaching of the basic course in Organic Chemistry to a new higher level introducing for the first time the functional principle in studying of organic compounds. Thus, this course became an example of a contemporary modern course in the field of chemistry. Prof. Ivanov's high teaching abilities from both methodical and scientific points of view were appreciated by the whole teaching staff and his numerous students and visiting collaborators. An important role in the formation of well trained experts can be attributed to Prof. Christo Ivanov's specialized course "Contemporary methods of Organic Synthesis".

Being an erudite, a talented teacher and a man of vision, Prof. Ivanov created a stimulating scientific atmosphere within the teachers in the Department of Organic Chemistry as well as in the whole Faculty of Chemistry. The high achievements of Prof. Ivanov in science and teaching have brought him the highest awards such as the Cyril-and-Methodius medal (1st degree), the People's-Republic-of-Bulgaria medal (1st degree), and the Plaque with Necklace of the "St. Kliment Ohridski" University of Sofia.