Examples:

• After losing the race, he claimed he didn't want to win anyway; it was just sour grapes.
• She dismissed the new manager's achievements as sour grapes because she didn't get the promotion.
• His negative comments about her were just sour grapes because she turned down his advances.
• He described the investment opportunity as sour grapes after he missed out on the chance to buy stocks at a low price.
• The student's criticism of the top scorer's performance was nothing more than sour grapes.
• The losing team's coach blamed the referees for their defeat, but it was just sour grapes.
• When their competitor launched a successful product, they dismissed it as sour grapes, claiming it was inferior to their own.
• After losing the bidding war for the house, they called the property overpriced as sour grapes.
• Her remarks about the wealthy neighborhood were seen as sour grapes because she couldn't afford to live there.
• When his artwork wasn't selected for the exhibition, he dismissed it as sour grapes, claiming the judges had no taste.