We would like to purchase Bitcoin (1-100 BTC) using Ethereum (ETH)

[Jujupanama]

All interested Sellers kindly P.M the Amount you wish to sell

All trades under Escrow buyer / seller protection

[akes2090]

All interested Sellers kindly P.M the Amount you wish to sell

All trades under Escrow buyer / seller protection

I would advise you to use one of the reputable crypto exchanges (OKEx, Binance, Bitfinex etc...) for this.
Note: This is not a "purchase" but an exchange.

I think you might even be able to exchange ETH for BTC if you have a Blockchain.info wallet (subject to correction).

[Lovecove]

I agree.

It's very easy to sign up for binance, no ID required. But if you're trying to trade higher volumes, like 100 BTC, they start getting meticulous and require gov docs.