I was an undergrad student with Professor X a few years back. Prof. X used to be a co-author in all the publications with Prof. Y. Prof. Y is very popular in the field.
Now, I am working in a university. I have keen interest to work with Prof. Y on a few problems of interest.
I have less idea on how to collaborate in such a situation where I don't have indirect contact apriori. The option that I have is to send a mail to him which looks as follows:
Subject: Request for collaboration -- Problem A and Problem B
Dear Prof. Y
I have learned about you from Prof. X during my works with him.
I have gone through your recent papers: [this] and [this]. I am good in Method1 and Method2 which could suitably address your problem.
My recent works can be found in [this profile link].
Looking forward to hearing from you.
-- [my signature]
Is this approach a suitable for my collaboration with Prof. Y?
Update: I had sent an email to Prof. Y after incorporating the suggestions from the fellow academia.SE community members here. I got a response from Prof. Y and looks like he is also interested in working together.