| 摘要 |
1330468 Ortho esters CASTROL Ltd 16 Dec 1970 [16 Dec 1969] 61301/69 Heading C2C [Also in Division C5] Ortho esters of the formulµ A and B: where R<SP>1</SP> is hydrogen, C 1-5 alkyl or the same as OR<SP>2</SP>; R<SP>2</SP> is C 1-4 alkyl, oxyalkylene glycol monoether or polyoxyalkylene glycol monoether having 2-20 oxyalkylene units, with the proviso that at least one R<SP>2</SP> is an oxyalkylene glycol monoether or polyoxyalkylene glycol monoether radical; and R<SP>3</SP> is C 1-12 alkylene, provided that R<SP>1</SP> is the same as OR<SP>2</SP> or R<SP>3</SP> is a group -O-(R<SP>4</SP>O) x - where each R<SP>4</SP> is C 2-8 alkylene and x is an integer of 1-6, may be made by transesterification between an alkyl ortho ester and an appropriate alcohol. |
