Alleghany Corp. said it signed an agreement to purchase Sacramento Savings & Loan Assn. of Sacramento and two related companies from the H.N. and Frances C. Berger Foundation for $150 million cash . . . Independent film producer Pathe Communications said it halted negotiations for the purchase of a $6-million interest in Kings Road Entertainment . . . The Transportation Department gave final approval to Federal Express Corp.'s takeover of the Flying Tigers air cargo service on the condition that Federal give up its U.S.-Japan small package service . . . . . . American Airlines said it has reached a contract agreement in principle with the Transport Workers Union, which represents 23,000 ground service personnel and mechanics . . . Sears, Roebuck & Co. said it is moving its catalogue operations from the landmark downtown Sears Tower in Chicago to a company-owned building in suburban Skokie . . . Chase Manhattan Bank said all its credit card accounts will leap to a 19.8% annual percentage interest rate from 17.5% on June 1. . . . Owners of America's mid-size, privately held businesses pay themselves an average of $151,000 annually in direct and indirect compensation, according to a study of middle market companies by Geneva Cos., an Irvine-based financial services organization that studied 2,500 firms with annual revenue from $1 million to $100 million.