You can only legally gamble online in Singapore at the Singapore Pools, where you can bet on sports (like horse racing) and play lotteries.

Instead, it's typically because either the credit card issuer or the sportsbook prohibits the use. Many credit card issuers simply don't consider gambling an acceptable purchase they may see it as too risky.

The short answer is "no". You can use your credit card to get a cash advance and then use the money to buy chips (or anything else of course) but you are probably already aware of how expensive this type of transaction is. Slot machines accept cash and "TITO" tickets.