Protection of functional groups during reaction and their subsequent restoration

US4111933A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Heiner Eckert · Munich, DE
• Ivar Ugi · Munich, DE
• Hans-Joachim Kabbe

Key dates

• Filing date: Apr 28, 1977
• Grant date: Sep 5, 1978
• Expiry date: Apr 28, 1997

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08K5/005
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

In the process for preparing an organic compound of the formula EQU A' -- X in which PA1 X is an amino group, a hydroxyl group or a carboxyl group, and PA1 A' is the remainder of the molecule, from an organic compound of the formula EQU A -- X in which PA1 A is the remainder of the molecule which can undergo reaction to form A', by converting A -- X into a compound of the formula EQU A -- Z -- COOR in which PA1 Z is --NH--, --O-- or a direct C--C bond, and PA1 R is a radical of the formula ##STR1## IN WHICH Y is a direct C--C single bond, the --CH.dbd.CH-- group or an arylene group, PA1 R.sup.1 to R.sup.4 each independently is hydrogen, halogen or an alkyl, aryl, aralkyl, alkoxycarbonyl, alkylaminocarbonyl, arylaminocarbonyl or cycloalkylaminocarbonyl radical, or PA1 R.sup.1 + r.sup.2 and R.sup.3 + R.sup.4 each independently completes a 5- or 6-membered carbocyclic ring, or PA1 R.sup.1 and R.sup.3 conjointly with the grouping --C--Y--C-- forms a carbocyclic ring with 5 or 6 carbon atoms, and Hal is halogen, Thereby to protect X, then converting A -- Z -- COOR into a compound of the formula EQU A' -- Z -- COOR and then treating the compound A' -- Z -- COOR to restore the group X, th…