Johnson Matthey's incoming finance boss Robert Macleod has signalled his commitment to his new employers by spending £37,000 on shares in the speciality chemicals company.He bought 3,000 at 1,236p a time, his first purchase of shares in the company, which refines platinum and makes catalysts for cars.Macleod joined the board on June 22 and will take over as finance director in September when J N Sheldrick steps down from the role.Macleod served as finance director of design and engineering consultancy group WS Atkins from 2004.Shares in Johnson Matthey fell sharply towards the end of last year in line with the turmoil that plagued global markets, but have since rallied. They are down by about 25%-30% on the year.Top Director BuysDigital Marketing (DIGI) Director name: Mr Keith SadlerAmount purchased: 150,000 @ 38.20p Value: £57,300Johnson Matthey (JMAT) Director name: Mr Robert MacLeodAmount purchased: 3,000 @ 1,236.00p Value: £37,080Top Director Sells