Oakland-based Kaiser Aluminum & Chemical said it completed the sale of its European subsidiary to Hoogovens Groep, resulting in an after-tax gain of about $45 million. . . . Jefferies Group, Los Angeles, said its board of directors authorized the purchase, from time to time, of up to 1 million shares of its common stock or the equivalent amount of its 8.5% convertible debentures. . . . Minneapolis-based Lieberman Enterprises, which is 54% owned by a unit of Carolco Pictures of Los Angeles, has sold its home video distribution division, Home Entertainment Distributors, to Ingram Distribution Group of Nashville, Tenn. . . . Bank of Boston Corp., the nation's 15th-largest bank holding company, said it has agreed to buy BankVermont Corp. in a stock swap valued at around $60 million.