Shares of crypto exchange Coinbase Global Inc (NASDAQ:COIN) were trading lower after the market close on Tuesday after the company announced a proposed private offering. What Happened: Coinbase said it intended to offer $1 billion worth of Convertible Senior Notes due 2030 in a private offering to institutional buyers. The company also expected to grant the initial purchasers a 30-day window to purchase up to an additional $150 million of the notes. The net proceeds from the offering will be used to repay at maturity, or repurchase or redeem prior to maturity, its outstanding 0.50% Convertible…