00:01
So in this question, they have given the structures and you have to write the absolute configuration.
00:07
That is r &s nomenclature and r &s nomenclature decided by, you know, khan, ingold and prolonged system, best on the priority of the group.
00:18
Okay.
00:19
Then whenever there is a rotation of a group from 1 to 4 in a clockwise manner, then it is assigned as a r configuration.
00:26
And when rotation from 1 to 4th groove it is an anticlockwise manner it is assigned as s configuration of course first priority group okay having more atomic number and least priority group has less atomic number now you know in this case you know oh got a first priority then this carbon chain got a second priority this methyl growth third and this is 4.
01:00
So this is moving in anti -clockwise manner and that's why its configuration is yes.
01:06
Then in this case, o .h got a first priority.
01:09
This is second, then methyl third and hydrogen fourth.
01:12
Now in this case, you know, it is moving in a clockwise manner.
01:17
That is 1, 2, 3.
01:19
But hydrogen is coming towards the observer or coming above the plane.
01:25
So actually 1, 2, 3 moving in a clockwise manner.
01:29
So it should be taken as a r configuration...