Authors: Matthias Drieß | Peter Comba
Source: Angewandte Chemie International Edition (article, 2021-10-25)
Field: Chemistry — Physical and Theoretical Chemistry

Gottfried Huttner (1937–2021): Intellectual Craftsman, Meaning Maker and Generalist Gottfried Huttner, formerly Professor of Inorganic Chemistry at Heidelberg University, passed away on July 21, 2021. With his pioneering contributions, he sustainably enriched the fields of X-ray crystallography, organometallic chemistry and main group chemistry. He will be remembered as an outstanding researcher and charismatic teacher. What are these nice episodes was our question. He asked us to be patient and take notes from our conversation and now, where he could not complete this himself, give them to his academic friends and companions. He was bursting out with a lough and said “I enjoy remembering my school days. I was an alert little boy and took up the various subjects with ease. With many of the topics I felt like a fish in the water: classical languages, literature, Mozart, piano lessons, math, the sciences and others.” Why then was he deciding for chemistry. “A good question”, was his answer, “it could also have been math or physics, which I enjoyed musingly.” His father, a chemist himself, instigated his fascination for chemistry and indorsed its various intellectual features. Born in the astrological sight Leo on August 1st 1937 in Ludwigshafen and grown up with Bavarian roots in Freising and Burghausen, chemistry was laid in his cradle. After a short intermezzo in mathematics and physics, he studied chemistry and, in the group of the Nobel laureate Ernst Otto Fischer (the “EO”), where he got his doctoral degree in inorganic chemistry in 1966, he was letting his scientific curiosity and passion come to life. While the synthesis of complexes with π acceptor ligands was the focus in his PhD project, X-ray crystallography of organo-transition-metal compounds were the center of attention of his habilitation thesis, finished at age 35. His work had many important consequences in the highly vital “EO School” because Huttner's expertise uncovered many structural secrets of novel organometallic types of compounds. Among others the ground-breaking structural analyses of various prototypes of new classes such as the π-bonded sandwich-type diarene metal complexes, borazine- and dewar-benzene complexes and Fischer carbines. “These were laborious studies, no routine in sight”, he said, “because the analyses had to be done with punch cards and without nowadays powerful computers, and an accurate analysis of a structure and its interpretation also with respect to bonding easily could cost a PhD thesis of three or four years”. “This is long ago”, he said, “I was attracted by improving the methods for fast data processing, and methods such as the fast Fourier transformation gave me much intellectual pleasure”. He proceeded to one of the first addresses in single crystal X-ray structural analyses of molecular systems also beyond Munich and has been able to crack many hard nuts in structural chemistry. Those who assume that the Huttner synthesis lab was falling asleep in this time are utterly wrong. In 1975, as fulminant surprise to the community, he presented the stabilization of mono-valent arsenic at a metal center in form of a phenylarsinidene complex. Subsequently, he and his group extended this concept successfully to phosphinidenes and other heavy pnictogenes with the result that Huttner's “inidene complexes” became marketable and inspired the community. In 1976, he obtained an offer to join the young university of Kaiserslautern, which he declined to accept an offer for a chair for Structural Inorganic Chemistry at the University of Konstanz. There, he extended his preparative toolbox for the stabilization of highly reactive molecular fragments and novel π-donor and -acceptor ligands such as diphosphorous (P2), diarsenic (As2), diantimony (Sb2) and dibismuth (Bi2) (!), which in contrast to N2 can act as 4-, 6- and even 8-electron donors. Here, he smilingly reminded us that the notorious Konstanz motto for new group members was: “I favorize a gearing between structural analysis and the art of synthesis. Those who want to measure and discover something extraordinary should be able to prepare something exciting and know and understand the handicraft and art of synthesis.” With the thriving intuition of Huttner it was only a small step from the “inidene complexes” as unsaturated building blocks to the targeted assembly of heteroelement metal cluster compounds. This vibrating new area offered unexpected insights into the dynamics of clusters, valence isomerism and applications toward the activation of small molecules at cluster surfaces. As the result of his everlasting passion for theoretical inorganic chemistry, he developed bonding models for the simplified but not too simple description of electronic structures of clusters with the new concept of the “breathing cluster”. Among many redox active iron-sulfur clusters was also a biomimetic functional model for the [FeFe] hydrogenase. In 1986, Gottfried Huttner accepted the offer from the University of Heidelberg for the chair of inorganic structural chemistry (succession of Hans Siebert). The chemistry of dimetallacumulenes of the type M=E=M with E=element of the group 14 to 16 started to flourish as well as that of the azide homologous RPPP- and RAsAsAs complexes as an homage to Theodor Curtius, the Heidelberg chemist and discoverer of the azide anion. It was the result of Gottfried Huttner's skill, verve, and determination for modernization that the attractivity of the Heidelberg Institute of Inorganic Chemistry rose such that in few years it advanced to a top school for young scientific talents. Six habilitations, four under his mentorship, were the result of a vibrating life at the institute. The friendly interaction and collaboration had an influence beyond the institute and was also obvious for invited guests. Lack of space in the research group was overcome by clever discussions with the administration that did not seek for expansion but rededication of a men's toilet into office space. Gottfried Huttner gained influence by creative science, farsighted structural planning and hard, determined work. He used the resulting power to educate those who he had selected to shape with them his ideas, create new ones and then help them to widely spread their wings to draw their own loops in science. Undergraduates, his own PhD students, young scientists preparing their habilitation, young colleagues that he attracted to Heidelberg and established scientists could write a book about this. He stroke his white beard and said: “I have often asked myself how an institution needs to be structured to allow a vibrant science culture to be developed beyond borders of particular subjects.” Our answer came instantaneously: “Just as your lab, a future forge, a think tank that continues to exist after the active scientific life and continues shining after death.” He advocated ideas on organization and support of science on the local and national scene as a member of the Heidelberg University Senate and the Board of the German Chemical Society. With initiatives and support for network programs and guest professorships, he has helped to define new research areas and integrate scientists. He was a brilliant and charismatic teacher. His lecture courses on symmetry and chemical space as well as spontaneous digressions in the seminar of advanced inorganic chemistry were captivating and encouraged students for further studies. He was a confessing critic of the new bachelor and master courses because of the early specialization, the tight organization and schooling. He also defined bibliometric data for the evaluation of scientific performance as absurd and was in favor of carefully reading the most important publications, chosen by the scientist to be evaluated, to get a good idea of its scientific background, creativity and efficiency. Chemistry, when performed such as in Gottfried Huttner's lab, is an intellectual handwork and exults fundamental science. For him, the design of a new molecule was art. Its synthesis demands for skilled craftmanship. The analysis of structure and reactivity requires deep insight into the physics of atoms and suitable algorithms for grasping the high complexity. Long before artificial intelligence became a promising tool, he employed neural networks for pattern recognition and conformational analysis. Many of his colleagues were less than enthusiastic about these ideas but he could not care less. As a conclusion in an essay of Johannes Hunger and Gottfried Huttner (Schriften der Mathematisch-Naturwissenschaftlichen Klasse der Heidelberger Akademie der Wissenschaften, Nr. 9, 2000) we read: “The sentence that imitation does not include learning seems to be contradicted if the imitation is learning.” To have been picked up by Gottfried Huttner to this world open for knowledge and to reflect with him for what the time is ripe was a privilege that we are now missing. Gottfried Huttner was intellectually restless, also after his retirement in 2005. From 2005 to 2009 he completed art studies at the Freie Kunstakademie Mannheim with a diploma painting. From 2009 to 2011 he was a student of his colleagues at the department of geosciences in Heidelberg and took up Turkish language and culture classes at the institute for islam science at Heidelberg University. At the end we looked at him and fell in silence. He smiled happily and seemed a little absent as we were saying goodbye. The authors declare no conflict of interest. Meaning (existential) ; Charisma ; Chemistry ; Philosophy ; Sociology ; Epistemology ; Theology History and advancements in chemistry