3i Infotech, Great Offshore and Hotel Leelaventure may be among companies that may fail to repay convertible bondholders when bonds mature this year while others may redeem by borrowing at high costs, or revising terms, says rating company Standard & Poor's. More than half of the 48 companies that are due to redeem an estimated $5 billion of convertible bonds in 2012 may default, S&P forecasts.