If you do not work in the purchasing department and you have no influence on decisions about dealings and purchases, then there is nothing wrong with you working as an intermediary between the businessmen and the company, because the basic principle is that it is permissible for a person to work as a broker in return for a set fee or for a percentage of the goods bought and sold, according to the agreement.
But that is conditional upon the goods and projects being things that are not forbidden according to sharee’ah.
But if a person’s work involves negotiating or dealing with these people, if he has some influence of the decisions that are made, then he has no right to take anything in return for his work, because he will be focusing on his own interests and not looking at the interests of the company for which he works, al-Bukhaari (7174) and Muslim (1832) narrated that Abu Humayd al-Saa’idi (may Allaah have mercy on him) said: The Prophet (peace and blessings of Allaah be upon him) appointed a man from Bani Asad who was called Ibn al-Lutbiyyah to collect zakaah. When he came he said: This is for you, and this was given to me (as a gift). The Messenger of Allaah (peace and blessings of Allaah be upon him) stood up on the minbar and praised and glorified Allaah, and said: “What is the matter with an agent whom I send, and he comes back and says, ‘This is for you and this was given to me’? Why doesn’t he sit in the house of his father or the house of his mother and see if he is given anything or not? By the One in Whose hand is the soul of Muhammad, no one of you gets anything from it (unlawfully), but he will bring it on the Day of Resurrection, carrying it on his neck, whether it is a groaning camel, a lowing cow or a bleating sheep.” Then he raised his arms until we saw the whiteness of his armpits, then he said: “O Allaah, have I conveyed (the message)?” three times.
It says in Fataawa al-Lajnah al-Daa’imah (13/131): It is permissible for the broker to take a set percentage of the price for which the goods are sold in return for finding buyers, and he may take it from the seller or the buyer according to the agreement, without any unfairness or harm. End quote.
See also the answer to question no. 66146
And Allaah knows best.