Sandmeyer. Traugott

Traugott Sandmeyer (1854-1922) was born in Wettingen. Switzerland, and received his Ph.D. at the University of Heidelberg. He spent his professional career doing pharmaceutical research at the Geigy Company in Basel,... 

Sandmeyer, T. Ber. Dtsch. Chem. Ges. 1884, 17, 1633. Traugott Sandmeyer (1854—1922) was bom in Wettingen, Switzerland. He apprenticed under Victor Meyer and Arthur Hantzsch although he never took a doctorate. He later spent 31 years at the firm J. R. Geigy, which is now part of Novartis. 

A few historical data are interesting to recall in order to show the role of serendipity in this field. Among the re-electron-excessive five-membered heteroaromatics with one heteroatom (CR)4X, thiophene has physico-chemical properties so similar to those of benzene that until 1882/3 it stayed hidden as an impurity in the benzene obtained from coal tar. Then Victor Meyer discovered it serendipitously at what is nowadays the Eidgenossische Technische Hochschule in Zurich, during a lecture demonstration by the assistant Traugott Sandmeyer in front of undergraduates. It was believed at that time that the deep blue color produced by heating benzene with isatin and concentrated sulfuric acid (the... 

Traugott Sandmeyer s 1896 discovery of acid glaucine red (38) led to the colorant better known as peacock blue, later employed extensively in multicolor printing. It came to prominence in the 1930s, with the introduction of flushed color production that enables retention of the required degree of fineness of pigment particles and provides uniform dispersion (Scheme 15)54,55. 

Traugott Sandmeyer described the synthesis of methyl and ethyl hypochlorites (refs. 2, 3) and suffered severe injuries. 

C6H5N2 + Cl- C HjCl + N2 This reaction was discovered by the German chemist Traugott Sandmeyer (1854-1922) in 1884. A variation of the reaction, in which the catalyst is freshly precipitated copper powder, was reported in 1890 by the German chemist Ludwig Gatterman (1860-1920). This is known as the Gatterman reaction (or Gat-terman-Sandmeyer reaction). 

The reaction was discovered in 1884 by the German chemist Traugott Sandmeyer (1854-1922). See also Gattehmann reaction. 

Traugott Sandmeyer (Wettingen, 15 September 1854-Zurich, 9 April 1922) was Victor Meyer s lecture assistant and participated in the discovery of thiophen (see p. 810). He discovered the Sandmeyer reaction for the preparation of halogen derivatives of aromatic hydrocarbons by warming a solution of a diazonium compound with cuprous chloride and hydrochloric acid, or cuprous bromide and hydrobromic acid, or with hydriodic acid or potassium... 

The reactivity of the isatin scaffold allows it to serve as a starting material for diverse applications from medicinal chemistry to total synthesis. At the turn of the 20th century Traugott Sandmeyer reported two methods for the synthesis of this essential building block. 

Another common transformation of diazonium salts is their conversion to aryl halides by reaction with cuprous salts (CuX), in what is known as the Sandmeyer reaction, named after Traugott Sandmeyer (Switzerland 1854-1922). This means that the Ar-NH2 ArX conversion is possible, where Ar = an aryl group. When 132 is treated with cuprous bromide (CuBr), the product is bromobenzene (18). The reaction works with many other cuprous salts as well, including cuprous chloride (CuCl). A variation of this reaction treats the diazonirun salt with cuprous cyanide (CuCN) to give a nitrile. In this manner, 4-methylanihne (24) is treated with HCI and NaN02 and then with CuCN to give 4-methyl-l-cyanobenzene (134). 

In 1884, the German chemist Traugott Sandmeyer found that diazonium ions react with nucleophiles supplied in the form of a Cu(I) salt. These nucleophiles replace the diazonium group and release nitrogen gas. These reactions are known collectively as the Sandmeyer reaction. 

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