UPDATE 1-Nasdaq to buy Thomson Reuters' PR, IR units

Dec 12 (Reuters) - Nasdaq OMX Group Inc said on Wednesday it would buy the investor relations, public relations, and multimedia solutions units of Thomson Reuters Corp for $390 million in cash to build its portfolio of products and services that do not depend on trading to generate revenue.

The transatlantic exchange operator said the deal would add to its earnings within the first 12 months, excluding transaction-related costs, and would generate "attractive returns" on capital.

Nasdaq said the Thomson Reuters units, which provide insight, analytics and communications solutions to more than 7,000 clients worldwide, will be integrated into Nasdaq OMX Corporate Solutions.

"In one acquisition, we accelerate and achieve our Corporate Solutions long-term objectives, while maintaining our balanced strategy of delivering value to shareholders," Bob Greifeld, Nasdaq's chief executive, said in a statement.

Nasdaq expects the acquisition will add to its non-transaction revenue base, which already stands at over 70 percent of the Company's total revenues.