SHANGHAI — A wealthy Chinese businessman and philanthropist known for his zany public stunts said on Tuesday that he was leading a group of investors seeking to acquire a large or controlling stake in The New York Times Company.

Shares in the Times Company jumped more than 4 percent to a five-year high on Monday, shortly after the businessman, Chen Guangbiao, hinted at his plans in a speech in southern China.

Arthur Sulzberger Jr., publisher of The New York Times, said in 2013 that the family that controls the paper is not interested in selling it.

In a phone interview on Tuesday, Mr. Chen said he had been thinking about “working with” The New York Times for years. Recently, he said, he had persuaded two businessmen, including a Hong Kong tycoon, to help him raise about $1 billion to snap up a large portion of the company, now valued at about $2.4 billion based on its stock price.