A synthesis has been developed for 2,7-dimethyl-1,8-di-o-tolylanthracene 4. The cis 4a and trans 4b isomers of this hydrocarbon can be separated and are stable to interconversion at temperatures below 200-degrees-C. The two enantiomers of the trans isomer 4b have chiral cavities and are expected to be useful precursors for chiral reagents or chiral catalysts.
Verfahren zur Herstellung von monobenzoylierten 1,8-Diaminoanthrachinonen
申请人:BAYER AG
公开号:EP0099071A2
公开(公告)日:1984-01-25
Verfahren zur Herstellung von gegebenenfalls substituiertem 1-Amino-8-aroylaminoanthrachinon durch Umsetzung von gegebenenfalls substituiertem 1,8-Diaminoanthrachinon mit einem Aroylhalogenid in Gegenwart eines organischen Lösungs- oder Verdünnungsmittels, eines säurebindenden Mittels und gegebenenfalls von Wasser, dadurch gekennzeichnet, daß man in Gegenwart von tertiären aliphatischen Aminoalkoholen und/oder quartären Ammoniumverbindungen arbeitet.
Accumulation in Dasuopu ice core in Qinghai-Tibet Plateau and solar activity
作者:Keqin Duan、Ninglian Wang、Yuefang Li、Weizheng Sun
DOI:10.1007/bf02884987
日期:2000.6
The time series of accumulation in recent 300 years correlated well with solar activity in Dasuopu ice core. Results of spectrum analysis on the accumulation time series of the Dasuopu ice core shows that there are some periods that coincide with the periods of solar activity. By comparing the long-time change trend of the accumulation in the Dasuopu ice core with various kinds of indexes of solar activity intensity, a negative correlation is found between the trend and solar activity.
Mayer; Guenther, Chemische Berichte, 1930, vol. 63, p. 1455,1462
作者:Mayer、Guenther
DOI:——
日期:——
Scholl; Ziegs, Chemische Berichte, 1934, vol. 67, p. 1746,1748
A synthesis has been developed for 2,7-dimethyl-1,8-di-o-tolylanthracene 4. The cis 4a and trans 4b isomers of this hydrocarbon can be separated and are stable to interconversion at temperatures below 200-degrees-C. The two enantiomers of the trans isomer 4b have chiral cavities and are expected to be useful precursors for chiral reagents or chiral catalysts.