CHICAGO — Mayor Rahm Emanuel’s appeal to the courts to end a six-day Chicago teachers strike set off a new round of recriminations Monday but did not appear to be leading to a quick resolution of the walkout that has left parents hunting for options for 350,000 students.

City attorneys asked a Cook County Circuit Court judge for an injunction Monday morning that would force teachers back into the classroom and end an acrimonious standoff with the nation’s third-largest school district. The suit claims that the strike violates state law because it threatens the safety of children and is based on issues other than pay and benefits.

But Judge Peter Flynn did not grant an immediate hearing, scheduling one for Wednesday morning, said Sarah Hamilton, Emanuel’s spokeswoman. That would be a day after Chicago Teachers Union delegates are set to vote again on whether to suspend the strike, the first in 25 years.

Union officials condemned Emanuel’s move as an act of vindictiveness by a “bullying” mayor. The union said the filing appears to be “a vindictive act” given that its delegates are set to vote on the contract today.

“This attempt to thwart our democratic process is consistent with Mayor Emanuel’s bullying behavior toward public school educators,” the union said.

Legal experts were split on whether Emanuel ultimately would be successful in persuading a judge to intervene.

Martin Malin, director of the Chicago-based Institute for Law and the Workplace at the Kent College of Law, said no judge in Illinois or, as far as he knows, in any other state, has ever granted an injunction during a teachers strike on the grounds it threatens public safety.

Such arguments have worked in strikes by garbage or water treatment workers, he said.

“There’s case law out there that the danger has to be clear and present and can’t just be speculative. So they have a very heavy burden of proof,” Malin said.

The request argues that the labor action is illegal because state law bars the union from striking on anything but economic issues, and that the work stoppage is focused instead on such issues as evaluations, layoffs and recall rights. The 700-page filing also contends the strike is a threat to health and safety because more than 80 percent of the 350,000 public students rely on school meals for their basic nutrition.

The filing states 50,000 others, including autistic students, depend on special instruction. And out of school, children are more prone to fall victim to violence, the filing states.

“At a critical time in their lives, a vulnerable population has been cast adrift by the CTU’s decision to close down the schools, with consequent grave implications for the residents of the city of Chicago,” the city suit states.

The union and school leaders appeared headed toward a resolution at the end of last week, saying they were optimistic that students in the nation’s third-largest school district would be back in class by Monday. But teachers uncomfortable with a tentative contract offer decided Sunday to remain on strike, saying they need more time to review a complicated proposal.

Emanuel pointedly responded by threatening legal action, saying the union was using school children as “pawns” in the midst of internal dispute about whether to accept the contract. After repeatedly calling the walkout unnecessary and “a strike of choice,” he called the union’s failure to act Sunday “a delay of choice.”

Working mom Dequita Wade said that when the strike started, she sent her son 15 miles away to a cousin’s house so he wouldn’t be left unsupervised in a neighborhood known for violent crime and gangs. She was hoping the sides would work things out quickly.

“You had a whole week. This is beginning to be ridiculous.”