naming of hydrocarbon

Question

CASE (I)
Give a pentane
有methyl,chloro,bromo
許中間個3個C
naming的次序係點?
係按字母最頭的次序name?
還是怎樣?

CASE (II)
GIve a pentan-1-ol
有methyl,chloro,bromo
許中間個3個C
naming的次序係點??

CASE(III)
GIve a pentanoic acid
有methyl,chloro,bromo
許中間個3個C
naming的次序係點??

Answer 1

case (i)
it depends on the alphabetic order.
it should be X-bromo-Y-chloro-Z-methylpentane (X,Y,Z are positive integers)
you better start counting the carbon where bromine attached to.

case(ii)
it depends on the location of -OH.
the carbon where -OH attached to should be count for the first.
but the naming is still depend on the alphabetic order.
X-bromo-Y-chloro-Z-methylpentan-1-ol (X,Y,Z are positive integers)

case(iii)
it depends on the location of -COOH.
the carbon of -COOH should be count for the first.
but the naming is still depend on the alphabetic order.
X-bromo-Y-chloro-Z-methylpentanoic acid (X,Y,Z are positive integers)

Answer 2

三個 cases 入面，methyl, chloro 同埋 bromo o既命名次序如下---
如果係英文：就一定要跟英文字母排列，即 bromo-chloro-methyl
如果係中文：可以跟字母，或者按照佢地o既結構排列，最簡單行先，所以次序會係 chloro-bromo-methyl

Case (II)
無論係中英文，都一定要連住 -OH o既 C 係第一個位。

Case (III)
就一定要係 -COOH 個 C 係第一位。